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Linux/WL1837MOD: Latency/PING jumps from low latency (5ms) to high latency in steps of approx. 120ms

Part Number: WL1837MOD
Other Parts Discussed in Thread: WL1837

Tool/software: Linux

Hi all,

I am testing the WL1837 for a 5GHz point to point application that requires a low and stable latency.

We bought two Beaglebone blacks and two Wireless connectivity capes from element14 for this purpose.

I installed both from the TI SDK version 4.01.00.06.

One is setup as AP (master) and as client (slave)

The problem is that the test shows a strange behaviour.

It seems that we get low roundtrip latency of approx. 5ms but occasionally the latency goes to 110-130 or 220-250.

It looks like when somethings goes wrong there is a 120ms wait period and we get one or two of these.

As you can see from the plots of pings over time and histograms the pings are distributed in 0-10, 110-130 or 220-250.

My first thought was that it is retransmission on the physical side that causes 120ms delay and we have either 0, 1 or 2 of these.

Although I think a wait period of 120ms is rather long.

The CPU load is also plotted in the graph but the load is never very high.

 

Can anyone explain me why this behaviour is seen and hopefully how to remove or reduce it.

The boards are setup as following:

On the master I use the following command to setup the AP (I attached hostapd.conf)

hostapd -dd hostapd.conf &

 

On the slave I simply connect using the TI scripts (I tried other approaches but with the same result).

I also disabled power saving on the slave to get a good ping. See commands below.

./sta_start.sh

./sta_connect-ex.sh SitaraAP

iw wlan0 set power_save off

 

I also tried to connect them in P2P mode with the same result.

Can anyone explain what is going on here and how to fix it?

Best Regards,

Erik

##### hostapd configuration file ##############################################
# Empty lines and lines starting with # are ignored
#
# Copyright (C) {2011} Texas Instruments Incorporated - http://www.ti.com/
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# 	http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and  
# limitations under the License.

# AP netdevice name (without 'ap' postfix, i.e., wlan0 uses wlan0ap for
# management frames); ath0 for madwifi
interface=wlan0

# In case of madwifi, atheros, and nl80211 driver interfaces, an additional
# configuration parameter, bridge, may be used to notify hostapd if the
# interface is included in a bridge. This parameter is not used with Host AP
# driver. If the bridge parameter is not set, the drivers will automatically
# figure out the bridge interface (assuming sysfs is enabled and mounted to
# /sys) and this parameter may not be needed.
#
# For nl80211, this parameter can be used to request the AP interface to be
# added to the bridge automatically (brctl may refuse to do this before hostapd
# has been started to change the interface mode). If needed, the bridge
# interface is also created.
#bridge=br0

# Driver interface type (hostap/wired/madwifi/test/none/nl80211/bsd);
# default: hostap). nl80211 is used with all Linux mac80211 drivers.
# Use driver=none if building hostapd as a standalone RADIUS server that does
# not control any wireless/wired driver.
driver=nl80211

# hostapd event logger configuration
#
# Two output method: syslog and stdout (only usable if not forking to
# background).
#
# Module bitfield (ORed bitfield of modules that will be logged; -1 = all
# modules):
# bit 0 (1) = IEEE 802.11
# bit 1 (2) = IEEE 802.1X
# bit 2 (4) = RADIUS
# bit 3 (8) = WPA
# bit 4 (16) = driver interface
# bit 5 (32) = IAPP
# bit 6 (64) = MLME
#
# Levels (minimum value for logged events):
#  0 = verbose debugging
#  1 = debugging
#  2 = informational messages
#  3 = notification
#  4 = warning
#
logger_syslog=-1
logger_syslog_level=2
logger_stdout=-1
logger_stdout_level=2

# Interface for separate control program. If this is specified, hostapd
# will create this directory and a UNIX domain socket for listening to requests
# from external programs (CLI/GUI, etc.) for status information and
# configuration. The socket file will be named based on the interface name, so
# multiple hostapd processes/interfaces can be run at the same time if more
# than one interface is used.
# /var/run/hostapd is the recommended directory for sockets and by default,
# hostapd_cli will use it when trying to connect with hostapd.
ctrl_interface=/var/run/hostapd
# Access control for the control interface can be configured by setting the
# directory to allow only members of a group to use sockets. This way, it is
# possible to run hostapd as root (since it needs to change network
# configuration and open raw sockets) and still allow GUI/CLI components to be
# run as non-root users. However, since the control interface can be used to
# change the network configuration, this access needs to be protected in many
# cases. By default, hostapd is configured to use gid 0 (root). If you
# want to allow non-root users to use the contron interface, add a new group
# and change this value to match with that group. Add users that should have
# control interface access to this group.
#
# This variable can be a group name or gid.
#ctrl_interface_group=wheel

##### IEEE 802.11 related configuration #######################################

# SSID to be used in IEEE 802.11 management frames
ssid=SitaraAP
# Alternative formats for configuring SSID
# (double quoted string, hexdump, printf-escaped string)
#ssid2="test"
#ssid2=74657374
#ssid2=P"hello\nthere"

# Country code (ISO/IEC 3166-1). Used to set regulatory domain.
# Set as needed to indicate country in which device is operating.
# This can limit available channels and transmit power.
country_code=DK

# Enable IEEE 802.11d. This advertises the country_code and the set of allowed
# channels and transmit power levels based on the regulatory limits. The
# country_code setting must be configured with the correct country for
# IEEE 802.11d functions.
# (default: 0 = disabled)
ieee80211d=1

# Enable IEEE 802.11h. This enables radar detection and DFS support if
# available. DFS support is required on outdoor 5 GHz channels in most countries
# of the world. This can be used only with ieee80211d=1.
# (default: 0 = disabled)
ieee80211h=1

# Operation mode (a = IEEE 802.11a, b = IEEE 802.11b, g = IEEE 802.11g,
# Default: IEEE 802.11b
hw_mode=a

# Channel number (IEEE 802.11)
# (default: 0, i.e., not set)
# Please note that some drivers do not use this value from hostapd and the
# channel will need to be configured separately with iwconfig.
# When set to 0, automatic channel selection will be engaged. A channel
# will be selected from the desired hw_mode.
channel=40

# Automatic channel selection (ACS) whitelist
# (default: not set)
# Allow only these channels in automatic channel selection
# acs_whitelist=1 2 3 4 5 6 7 8 9 10 11

# Automatic channel selection (ACS) blacklist
# (default: not set)
# Don't allow these channels in automatic channel selection
# acs_blacklist=1 2 3 4 5 6 7 8 9 10 11
# Sync channel to previous operational APs
# (default: 0)
# Set to 1 in order to sync the channel of the current AP to the
# channel of an operational radio on the same PHY. Note that this
# applies to the 40Mhz operating channel (primary + secondary)
ap_channel_sync=1

# Beacon interval in kus (1.024 ms) (default: 100; range 15..65535)
beacon_int=100

# DTIM (delivery traffic information message) period (range 1..255):
# number of beacons between DTIMs (1 = every beacon includes DTIM element)
# (default: 2)
dtim_period=2

# Maximum number of stations allowed in station table. New stations will be
# rejected after the station table is full. IEEE 802.11 has a limit of 2007
# different association IDs, so this number should not be larger than that.
# (default: 2007)
max_num_sta=10

# RTS/CTS threshold; 2347 = disabled (default); range 0..2347
# If this field is not included in hostapd.conf, hostapd will not control
# RTS threshold and 'iwconfig wlan# rts <val>' can be used to set it.
#rts_threshold=2347

# Fragmentation threshold; 2346 = disabled (default); range 256..2346
# If this field is not included in hostapd.conf, hostapd will not control
# fragmentation threshold and 'iwconfig wlan# frag <val>' can be used to set
# it.
#fragm_threshold=2346

# Rate configuration
# Default is to enable all rates supported by the hardware. This configuration
# item allows this list be filtered so that only the listed rates will be left
# in the list. If the list is empty, all rates are used. This list can have
# entries that are not in the list of rates the hardware supports (such entries
# are ignored). The entries in this list are in 100 kbps, i.e., 11 Mbps = 110.
# If this item is present, at least one rate have to be matching with the rates
# hardware supports.
# default: use the most common supported rate setting for the selected
# hw_mode (i.e., this line can be removed from configuration file in most
# cases)
supported_rates=10 20 55 110 60 90 120 180 240 360 480 540

# Basic rate set configuration
# List of rates (in 100 kbps) that are included in the basic rate set.
# If this item is not included, usually reasonable default set is used.
#basic_rates=10 20
#basic_rates=10 20 55 110
#basic_rates=60 120 240
basic_rates=10 20 55 110 60 120 240

# Short Preamble
# This parameter can be used to enable optional use of short preamble for
# frames sent at 2 Mbps, 5.5 Mbps, and 11 Mbps to improve network performance.
# This applies only to IEEE 802.11b-compatible networks and this should only be
# enabled if the local hardware supports use of short preamble. If any of the
# associated STAs do not support short preamble, use of short preamble will be
# disabled (and enabled when such STAs disassociate) dynamically.
# 0 = do not allow use of short preamble (default)
# 1 = allow use of short preamble
preamble=1

# Station MAC address -based authentication
# Please note that this kind of access control requires a driver that uses
# hostapd to take care of management frame processing and as such, this can be
# used with driver=hostap or driver=nl80211, but not with driver=madwifi.
# 0 = accept unless in deny list
# 1 = deny unless in accept list
# 2 = use external RADIUS server (accept/deny lists are searched first)
macaddr_acl=0

# Accept/deny lists are read from separate files (containing list of
# MAC addresses, one per line). Use absolute path name to make sure that the
# files can be read on SIGHUP configuration reloads.
#accept_mac_file=/etc/hostapd.accept
#deny_mac_file=/etc/hostapd.deny

# IEEE 802.11 specifies two authentication algorithms. hostapd can be
# configured to allow both of these or only one. Open system authentication
# should be used with IEEE 802.1X.
# Bit fields of allowed authentication algorithms:
# bit 0 = Open System Authentication
# bit 1 = Shared Key Authentication (requires WEP)
auth_algs=3

# Send empty SSID in beacons and ignore probe request frames that do not
# specify full SSID, i.e., require stations to know SSID.
# default: disabled (0)
# 1 = send empty (length=0) SSID in beacon and ignore probe request for
#     broadcast SSID
# 2 = clear SSID (ASCII 0), but keep the original length (this may be required
#     with some clients that do not support empty SSID) and ignore probe
#     requests for broadcast SSID
ignore_broadcast_ssid=0

# Additional vendor specfic elements for Beacon and Probe Response frames
# This parameter can be used to add additional vendor specific element(s) into
# the end of the Beacon and Probe Response frames. The format for these
# element(s) is a hexdump of the raw information elements (id+len+payload for
# one or more elements)
#vendor_elements=dd0411223301

# TX queue parameters (EDCF / bursting)
# tx_queue_<queue name>_<param>
# queues: data0, data1, data2, data3, after_beacon, beacon
#		(data0 is the highest priority queue)
# parameters:
#   aifs: AIFS (default 2)
#   cwmin: cwMin (1, 3, 7, 15, 31, 63, 127, 255, 511, 1023)
#   cwmax: cwMax (1, 3, 7, 15, 31, 63, 127, 255, 511, 1023); cwMax >= cwMin
#   burst: maximum length (in milliseconds with precision of up to 0.1 ms) for
#          bursting
#
# Default WMM parameters (IEEE 802.11 draft; 11-03-0504-03-000e):
# These parameters are used by the access point when transmitting frames
# to the clients.
#
# Low priority / AC_BK = background
tx_queue_data3_aifs=7
tx_queue_data3_cwmin=15
tx_queue_data3_cwmax=1023
tx_queue_data3_burst=0

# Note: for IEEE 802.11b mode: cWmin=31 cWmax=1023 burst=0
#
# Normal priority / AC_BE = best effort
tx_queue_data2_aifs=3
tx_queue_data2_cwmin=15
tx_queue_data2_cwmax=63
tx_queue_data2_burst=0

# Note: for IEEE 802.11b mode: cWmin=31 cWmax=127 burst=0
#
# High priority / AC_VI = video
tx_queue_data1_aifs=1
tx_queue_data1_cwmin=7
tx_queue_data1_cwmax=15
tx_queue_data1_burst=3.0

# Note: for IEEE 802.11b mode: cWmin=15 cWmax=31 burst=6.0
#
# Highest priority / AC_VO = voice
tx_queue_data0_aifs=1
tx_queue_data0_cwmin=3
tx_queue_data0_cwmax=7
tx_queue_data0_burst=1.5
# Note: for IEEE 802.11b mode: cWmin=7 cWmax=15 burst=3.3

# 802.1D Tag (= UP) to AC mappings
# WMM specifies following mapping of data frames to different ACs. This mapping
# can be configured using Linux QoS/tc and sch_pktpri.o module.
# 802.1D Tag	802.1D Designation	Access Category	WMM Designation
# 1		BK			AC_BK		Background
# 2		-			AC_BK		Background
# 0		BE			AC_BE		Best Effort
# 3		EE			AC_BE		Best Effort
# 4		CL			AC_VI		Video
# 5		VI			AC_VI		Video
# 6		VO			AC_VO		Voice
# 7		NC			AC_VO		Voice
# Data frames with no priority information: AC_BE
# Management frames: AC_VO
# PS-Poll frames: AC_BE

# Default WMM parameters (IEEE 802.11 draft; 11-03-0504-03-000e):
# for 802.11a or 802.11g networks
# These parameters are sent to WMM clients when they associate.
# The parameters will be used by WMM clients for frames transmitted to the
# access point.
#
# note - txop_limit is in units of 32microseconds
# note - acm is admission control mandatory flag. 0 = admission control not
# required, 1 = mandatory
# note - here cwMin and cmMax are in exponent form. the actual cw value used
# will be (2^n)-1 where n is the value given here
#
wme_enabled=1

#
# WMM-PS Unscheduled Automatic Power Save Delivery [U-APSD]
# Enable this flag if U-APSD supported outside hostapd (eg., Firmware/driver)
uapsd_advertisement_enabled=1

#
# Low priority / AC_BK = background
wme_ac_bk_cwmin=4
wme_ac_bk_cwmax=10
wme_ac_bk_aifs=7
wme_ac_bk_txop_limit=0
wme_ac_bk_acm=0

# Note: for IEEE 802.11b mode: cWmin=5 cWmax=10
#
# Normal priority / AC_BE = best effort
wme_ac_be_aifs=3
wme_ac_be_cwmin=4
wme_ac_be_cwmax=10
wme_ac_be_txop_limit=0
wme_ac_be_acm=0

# Note: for IEEE 802.11b mode: cWmin=5 cWmax=7
#
# High priority / AC_VI = video
wme_ac_vi_aifs=2
wme_ac_vi_cwmin=3
wme_ac_vi_cwmax=4
wme_ac_vi_txop_limit=94
wme_ac_vi_acm=0

# Note: for IEEE 802.11b mode: cWmin=4 cWmax=5 txop_limit=188
#
# Highest priority / AC_VO = voice
wme_ac_vo_aifs=2
wme_ac_vo_cwmin=2
wme_ac_vo_cwmax=3
wme_ac_vo_txop_limit=47
wme_ac_vo_acm=0
# Note: for IEEE 802.11b mode: cWmin=3 cWmax=4 burst=102

# Static WEP key configuration
#
# The key number to use when transmitting.
# It must be between 0 and 3, and the corresponding key must be set.
# default: not set
#wep_default_key=0

# The WEP keys to use.
# A key may be a quoted string or unquoted hexadecimal digits.
# The key length should be 5, 13, or 16 characters, or 10, 26, or 32
# digits, depending on whether 40-bit (64-bit), 104-bit (128-bit), or
# 128-bit (152-bit) WEP is used.
# Only the default key must be supplied; the others are optional.
# default: not set
#wep_key0=123456789a
#wep_key1="vwxyz"
#wep_key2=0102030405060708090a0b0c0d
#wep_key3=".2.4.6.8.0.23"

# Station inactivity limit
#
# If a station does not send anything in ap_max_inactivity seconds, an
# empty data frame is sent to it in order to verify whether it is
# still in range. If this frame is not ACKed, the station will be
# disassociated and then deauthenticated. This feature is used to
# clear station table of old entries when the STAs move out of the
# range.
#
# The station can associate again with the AP if it is still in range;
# this inactivity poll is just used as a nicer way of verifying
# inactivity; i.e., client will not report broken connection because
# disassociation frame is not sent immediately without first polling
# the STA with a data frame.
# default: 300 (i.e., 5 minutes)
ap_max_inactivity=10000

#
# The inactivity polling can be disabled to disconnect stations based on
# inactivity timeout so that idle stations are more likely to be disconnected
# even if they are still in range of the AP. This can be done by setting
# skip_inactivity_poll to 1 (default 0).
#skip_inactivity_poll=0

# Disassociate stations based on excessive transmission failures or other
# indications of connection loss. This depends on the driver capabilities and
# may not be available with all drivers.
disassoc_low_ack=1

# Maximum allowed Listen Interval (how many Beacon periods STAs are allowed to
# remain asleep). Default: 65535 (no limit apart from field size)
#max_listen_interval=100

# WDS (4-address frame) mode with per-station virtual interfaces
# (only supported with driver=nl80211)
# This mode allows associated stations to use 4-address frames to allow layer 2
# bridging to be used.
#wds_sta=1

# If bridge parameter is set, the WDS STA interface will be added to the same
# bridge by default. This can be overridden with the wds_bridge parameter to
# use a separate bridge.
#wds_bridge=wds-br0

# Client isolation can be used to prevent low-level bridging of frames between
# associated stations in the BSS. By default, this bridging is allowed.
#ap_isolate=1
##### IEEE 802.11n related configuration ######################################

# ieee80211n: Whether IEEE 802.11n (HT) is enabled
# 0 = disabled (default)
# 1 = enabled
# Note: You will also need to enable WMM for full HT functionality.
ieee80211n=1

# ht_capab: HT capabilities (list of flags)
# LDPC coding capability: [LDPC] = supported
# Supported channel width set: [HT40-] = both 20 MHz and 40 MHz with secondary
#	channel below the primary channel; [HT40+] = both 20 MHz and 40 MHz
#	with secondary channel below the primary channel
#	(20 MHz only if neither is set)
#	Note: There are limits on which channels can be used with HT40- and
#	HT40+. Following table shows the channels that may be available for
#	HT40- and HT40+ use per IEEE 802.11n Annex J:
#	freq		HT40-		HT40+
#	2.4 GHz		5-13		1-7 (1-9 in Europe/Japan)
#	5 GHz		40,48,56,64	36,44,52,60
#	(depending on the location, not all of these channels may be available
#	for use)
#	Please note that 40 MHz channels may switch their primary and secondary
#	channels if needed or creation of 40 MHz channel maybe rejected based
#	on overlapping BSSes. These changes are done automatically when hostapd
#	is setting up the 40 MHz channel.
# Spatial Multiplexing (SM) Power Save: [SMPS-STATIC] or [SMPS-DYNAMIC]
#	(SMPS disabled if neither is set)
# HT-greenfield: [GF] (disabled if not set)
# Short GI for 20 MHz: [SHORT-GI-20] (disabled if not set)
# Short GI for 40 MHz: [SHORT-GI-40] (disabled if not set)
# Tx STBC: [TX-STBC] (disabled if not set)
# Rx STBC: [RX-STBC1] (one spatial stream), [RX-STBC12] (one or two spatial
#	streams), or [RX-STBC123] (one, two, or three spatial streams); Rx STBC
#	disabled if none of these set
# HT-delayed Block Ack: [DELAYED-BA] (disabled if not set)
# Maximum A-MSDU length: [MAX-AMSDU-7935] for 7935 octets (3839 octets if not
#	set)
# DSSS/CCK Mode in 40 MHz: [DSSS_CCK-40] = allowed (not allowed if not set)
# PSMP support: [PSMP] (disabled if not set)
# L-SIG TXOP protection support: [LSIG-TXOP-PROT] (disabled if not set)
ht_capab=[SHORT-GI-20][GF]

# Require stations to support HT PHY (reject association if they do not)
#require_ht=1
##### IEEE 802.1X-2004 related configuration ##################################

# Require IEEE 802.1X authorization
#ieee8021x=1

# IEEE 802.1X/EAPOL version
# hostapd is implemented based on IEEE Std 802.1X-2004 which defines EAPOL
# version 2. However, there are many client implementations that do not handle
# the new version number correctly (they seem to drop the frames completely).
# In order to make hostapd interoperate with these clients, the version number
# can be set to the older version (1) with this configuration value.
#eapol_version=2

# Optional displayable message sent with EAP Request-Identity. The first \0
# in this string will be converted to ASCII-0 (nul). This can be used to
# separate network info (comma separated list of attribute=value pairs); see,
# e.g., RFC 4284.
#eap_message=hello
#eap_message=hello\0networkid=netw,nasid=foo,portid=0,NAIRealms=example.com

# WEP rekeying (disabled if key lengths are not set or are set to 0)
# Key lengths for default/broadcast and individual/unicast keys:
# 5 = 40-bit WEP (also known as 64-bit WEP with 40 secret bits)
# 13 = 104-bit WEP (also known as 128-bit WEP with 104 secret bits)
#wep_key_len_broadcast=5
#wep_key_len_unicast=5
# Rekeying period in seconds. 0 = do not rekey (i.e., set keys only once)
wep_rekey_period=0
# EAPOL-Key index workaround (set bit7) for WinXP Supplicant (needed only if
# only broadcast keys are used)
#eapol_key_index_workaround=0

# EAP reauthentication period in seconds (default: 3600 seconds; 0 = disable
# reauthentication).
#eap_reauth_period=3600

# Use PAE group address (01:80:c2:00:00:03) instead of individual target
# address when sending EAPOL frames with driver=wired. This is the most common
# mechanism used in wired authentication, but it also requires that the port
# is only used by one station.
#use_pae_group_addr=1
##### Integrated EAP server ###################################################

# Optionally, hostapd can be configured to use an integrated EAP server
# to process EAP authentication locally without need for an external RADIUS
# server. This functionality can be used both as a local authentication server
# for IEEE 802.1X/EAPOL and as a RADIUS server for other devices.

# Use integrated EAP server instead of external RADIUS authentication
# server. This is also needed if hostapd is configured to act as a RADIUS
# authentication server.
eap_server=1
# Path for EAP server user database
# If SQLite support is included, this can be set to "sqlite:/path/to/sqlite.db"
# to use SQLite database instead of a text file.
#eap_user_file=/etc/hostapd.eap_user

# CA certificate (PEM or DER file) for EAP-TLS/PEAP/TTLS
#ca_cert=/etc/hostapd.ca.pem

# Server certificate (PEM or DER file) for EAP-TLS/PEAP/TTLS
#server_cert=/etc/hostapd.server.pem

# Private key matching with the server certificate for EAP-TLS/PEAP/TTLS
# This may point to the same file as server_cert if both certificate and key
# are included in a single file. PKCS#12 (PFX) file (.p12/.pfx) can also be
# used by commenting out server_cert and specifying the PFX file as the
# private_key.
#private_key=/etc/hostapd.server.prv

# Passphrase for private key
#private_key_passwd=secret passphrase

# Enable CRL verification.
# Note: hostapd does not yet support CRL downloading based on CDP. Thus, a
# valid CRL signed by the CA is required to be included in the ca_cert file.
# This can be done by using PEM format for CA certificate and CRL and
# concatenating these into one file. Whenever CRL changes, hostapd needs to be
# restarted to take the new CRL into use.
# 0 = do not verify CRLs (default)
# 1 = check the CRL of the user certificate
# 2 = check all CRLs in the certificate path
#check_crl=1

# dh_file: File path to DH/DSA parameters file (in PEM format)
# This is an optional configuration file for setting parameters for an
# ephemeral DH key exchange. In most cases, the default RSA authentication does
# not use this configuration. However, it is possible setup RSA to use
# ephemeral DH key exchange. In addition, ciphers with DSA keys always use
# ephemeral DH keys. This can be used to achieve forward secrecy. If the file
# is in DSA parameters format, it will be automatically converted into DH
# params. This parameter is required if anonymous EAP-FAST is used.
# You can generate DH parameters file with OpenSSL, e.g.,
# "openssl dhparam -out /etc/hostapd.dh.pem 1024"
#dh_file=/etc/hostapd.dh.pem

# Fragment size for EAP methods
#fragment_size=1400

# Finite cyclic group for EAP-pwd. Number maps to group of domain parameters
# using the IANA repository for IKE (RFC 2409).
#pwd_group=19

# Configuration data for EAP-SIM database/authentication gateway interface.
# This is a text string in implementation specific format. The example
# implementation in eap_sim_db.c uses this as the UNIX domain socket name for
# the HLR/AuC gateway (e.g., hlr_auc_gw). In this case, the path uses "unix:"
# prefix. If hostapd is built with SQLite support (CONFIG_SQLITE=y in .config),
# database file can be described with an optional db=<path> parameter.
#eap_sim_db=unix:/tmp/hlr_auc_gw.sock
#eap_sim_db=unix:/tmp/hlr_auc_gw.sock db=/tmp/hostapd.db

# Encryption key for EAP-FAST PAC-Opaque values. This key must be a secret,
# random value. It is configured as a 16-octet value in hex format. It can be
# generated, e.g., with the following command:
# od -tx1 -v -N16 /dev/random | colrm 1 8 | tr -d ' '
#pac_opaque_encr_key=000102030405060708090a0b0c0d0e0f

# EAP-FAST authority identity (A-ID)
# A-ID indicates the identity of the authority that issues PACs. The A-ID
# should be unique across all issuing servers. In theory, this is a variable
# length field, but due to some existing implementations requiring A-ID to be
# 16 octets in length, it is strongly recommended to use that length for the
# field to provid interoperability with deployed peer implementations. This
# field is configured in hex format.
#eap_fast_a_id=101112131415161718191a1b1c1d1e1f

# EAP-FAST authority identifier information (A-ID-Info)
# This is a user-friendly name for the A-ID. For example, the enterprise name
# and server name in a human-readable format. This field is encoded as UTF-8.
#eap_fast_a_id_info=test server

# Enable/disable different EAP-FAST provisioning modes:
#0 = provisioning disabled
#1 = only anonymous provisioning allowed
#2 = only authenticated provisioning allowed
#3 = both provisioning modes allowed (default)
#eap_fast_prov=3

# EAP-FAST PAC-Key lifetime in seconds (hard limit)
#pac_key_lifetime=604800

# EAP-FAST PAC-Key refresh time in seconds (soft limit on remaining hard
# limit). The server will generate a new PAC-Key when this number of seconds
# (or fewer) of the lifetime remains.
#pac_key_refresh_time=86400

# EAP-SIM and EAP-AKA protected success/failure indication using AT_RESULT_IND
# (default: 0 = disabled).
#eap_sim_aka_result_ind=1

# Trusted Network Connect (TNC)
# If enabled, TNC validation will be required before the peer is allowed to
# connect. Note: This is only used with EAP-TTLS and EAP-FAST. If any other
# EAP method is enabled, the peer will be allowed to connect without TNC.
#tnc=1
##### RADIUS client configuration #############################################
# for IEEE 802.1X with external Authentication Server, IEEE 802.11
# authentication with external ACL for MAC addresses, and accounting

# The own IP address of the access point (used as NAS-IP-Address)
own_ip_addr=127.0.0.1
# Optional NAS-Identifier string for RADIUS messages. When used, this should be
# a unique to the NAS within the scope of the RADIUS server. For example, a
# fully qualified domain name can be used here.
# When using IEEE 802.11r, nas_identifier must be set and must be between 1 and
# 48 octets long.
#nas_identifier=ap.example.com

# RADIUS authentication server
#auth_server_addr=127.0.0.1
#auth_server_port=1812
#auth_server_shared_secret=secret

# RADIUS accounting server
#acct_server_addr=127.0.0.1
#acct_server_port=1813
#acct_server_shared_secret=secret

# Secondary RADIUS servers; to be used if primary one does not reply to
# RADIUS packets. These are optional and there can be more than one secondary
# server listed.
#auth_server_addr=127.0.0.2
#auth_server_port=1812
#auth_server_shared_secret=secret2
#
#acct_server_addr=127.0.0.2
#acct_server_port=1813
#acct_server_shared_secret=secret2

# Retry interval for trying to return to the primary RADIUS server (in
# seconds). RADIUS client code will automatically try to use the next server
# when the current server is not replying to requests. If this interval is set,
# primary server will be retried after configured amount of time even if the
# currently used secondary server is still working.
#radius_retry_primary_interval=600


# Interim accounting update interval
# If this is set (larger than 0) and acct_server is configured, hostapd will
# send interim accounting updates every N seconds. Note: if set, this overrides
# possible Acct-Interim-Interval attribute in Access-Accept message. Thus, this
# value should not be configured in hostapd.conf, if RADIUS server is used to
# control the interim interval.
# This value should not be less 600 (10 minutes) and must not be less than
# 60 (1 minute).
#radius_acct_interim_interval=600

# Request Chargeable-User-Identity (RFC 4372)
# This parameter can be used to configure hostapd to request CUI from the
# RADIUS server by including Chargeable-User-Identity attribute into
# Access-Request packets.
#radius_request_cui=1

# Dynamic VLAN mode; allow RADIUS authentication server to decide which VLAN
# is used for the stations. This information is parsed from following RADIUS
# attributes based on RFC 3580 and RFC 2868: Tunnel-Type (value 13 = VLAN),
# Tunnel-Medium-Type (value 6 = IEEE 802), Tunnel-Private-Group-ID (value
# VLANID as a string). vlan_file option below must be configured if dynamic
# VLANs are used. Optionally, the local MAC ACL list (accept_mac_file) can be
# used to set static client MAC address to VLAN ID mapping.
# 0 = disabled (default)
# 1 = option; use default interface if RADIUS server does not include VLAN ID
# 2 = required; reject authentication if RADIUS server does not include VLAN ID
#dynamic_vlan=0

# VLAN interface list for dynamic VLAN mode is read from a separate text file.
# This list is used to map VLAN ID from the RADIUS server to a network
# interface. Each station is bound to one interface in the same way as with
# multiple BSSIDs or SSIDs. Each line in this text file is defining a new
# interface and the line must include VLAN ID and interface name separated by
# white space (space or tab).
#vlan_file=/etc/hostapd.vlan

# Interface where 802.1q tagged packets should appear when a RADIUS server is
# used to determine which VLAN a station is on.  hostapd creates a bridge for
# each VLAN.  Then hostapd adds a VLAN interface (associated with the interface
# indicated by 'vlan_tagged_interface') and the appropriate wireless interface
# to the bridge.
#vlan_tagged_interface=eth0

# When hostapd creates a VLAN interface on vlan_tagged_interfaces, it needs
# to know how to name it.
# 0 = vlan<XXX>, e.g., vlan1
# 1 = <vlan_tagged_interface>.<XXX>, e.g. eth0.1
#vlan_naming=0

# Arbitrary RADIUS attributes can be added into Access-Request and
# Accounting-Request packets by specifying the contents of the attributes with
# the following configuration parameters. There can be multiple of these to
# add multiple attributes. These parameters can also be used to override some
# of the attributes added automatically by hostapd.
# Format: <attr_id>[:<syntax:value>]
# attr_id: RADIUS attribute type (e.g., 26 = Vendor-Specific)
# syntax: s = string (UTF-8), d = integer, x = octet string
# value: attribute value in format indicated by the syntax
# If syntax and value parts are omitted, a null value (single 0x00 octet) is
# used.
#
# Additional Access-Request attributes
# radius_auth_req_attr=<attr_id>[:<syntax:value>]
# Examples:
# Operator-Name = "Operator"
#radius_auth_req_attr=126:s:Operator
# Service-Type = Framed (2)
#radius_auth_req_attr=6:d:2
# Connect-Info = "testing" (this overrides the automatically generated value)
#radius_auth_req_attr=77:s:testing
# Same Connect-Info value set as a hexdump
#radius_auth_req_attr=77:x:74657374696e67

#
# Additional Accounting-Request attributes
# radius_acct_req_attr=<attr_id>[:<syntax:value>]
# Examples:
# Operator-Name = "Operator"
#radius_acct_req_attr=126:s:Operator

# Dynamic Authorization Extensions (RFC 5176)
# This mechanism can be used to allow dynamic changes to user session based on
# commands from a RADIUS server (or some other disconnect client that has the
# needed session information). For example, Disconnect message can be used to
# request an associated station to be disconnected.
#
# This is disabled by default. Set radius_das_port to non-zero UDP port
# number to enable.
#radius_das_port=3799
#
# DAS client (the host that can send Disconnect/CoA requests) and shared secret
#radius_das_client=192.168.1.123 shared secret here
#
# DAS Event-Timestamp time window in seconds
#radius_das_time_window=300
#
# DAS require Event-Timestamp
#radius_das_require_event_timestamp=1

##### RADIUS authentication server configuration ##############################

# hostapd can be used as a RADIUS authentication server for other hosts. This
# requires that the integrated EAP server is also enabled and both
# authentication services are sharing the same configuration.

# File name of the RADIUS clients configuration for the RADIUS server. If this
# commented out, RADIUS server is disabled.
#radius_server_clients=/etc/hostapd.radius_clients

# The UDP port number for the RADIUS authentication server
#radius_server_auth_port=1812

# Use IPv6 with RADIUS server (IPv4 will also be supported using IPv6 API)
#radius_server_ipv6=1
##### WPA/IEEE 802.11i configuration ##########################################

# Enable WPA. Setting this variable configures the AP to require WPA (either
# WPA-PSK or WPA-RADIUS/EAP based on other configuration). For WPA-PSK, either
# wpa_psk or wpa_passphrase must be set and wpa_key_mgmt must include WPA-PSK.
# Instead of wpa_psk / wpa_passphrase, wpa_psk_radius might suffice.
# For WPA-RADIUS/EAP, ieee8021x must be set (but without dynamic WEP keys),
# RADIUS authentication server must be configured, and WPA-EAP must be included
# in wpa_key_mgmt.
# This field is a bit field that can be used to enable WPA (IEEE 802.11i/D3.0)
# and/or WPA2 (full IEEE 802.11i/RSN):
# bit0 = WPA
# bit1 = IEEE 802.11i/RSN (WPA2) (dot11RSNAEnabled)
#wpa=1

# WPA pre-shared keys for WPA-PSK. This can be either entered as a 256-bit
# secret in hex format (64 hex digits), wpa_psk, or as an ASCII passphrase
# (8..63 characters) that will be converted to PSK. This conversion uses SSID
# so the PSK changes when ASCII passphrase is used and the SSID is changed.
# wpa_psk (dot11RSNAConfigPSKValue)
# wpa_passphrase (dot11RSNAConfigPSKPassPhrase)
#wpa_psk=0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef
#wpa_passphrase=secret passphrase

# Optionally, WPA PSKs can be read from a separate text file (containing list
# of (PSK,MAC address) pairs. This allows more than one PSK to be configured.
# Use absolute path name to make sure that the files can be read on SIGHUP
# configuration reloads.
#wpa_psk_file=/etc/hostapd.wpa_psk

# Optionally, WPA passphrase can be received from RADIUS authentication server
# This requires macaddr_acl to be set to 2 (RADIUS)
# 0 = disabled (default)
# 1 = optional; use default passphrase/psk if RADIUS server does not include
#	Tunnel-Password
# 2 = required; reject authentication if RADIUS server does not include
#	Tunnel-Password
#wpa_psk_radius=0

# Set of accepted key management algorithms (WPA-PSK, WPA-EAP, or both). The
# entries are separated with a space. WPA-PSK-SHA256 and WPA-EAP-SHA256 can be
# added to enable SHA256-based stronger algorithms.
# (dot11RSNAConfigAuthenticationSuitesTable)
#wpa_key_mgmt=WPA-PSK WPA-EAP

# Set of accepted cipher suites (encryption algorithms) for pairwise keys
# (unicast packets). This is a space separated list of algorithms:
# CCMP = AES in Counter mode with CBC-MAC [RFC 3610, IEEE 802.11i/D7.0]
# TKIP = Temporal Key Integrity Protocol [IEEE 802.11i/D7.0]
# Group cipher suite (encryption algorithm for broadcast and multicast frames)
# is automatically selected based on this configuration. If only CCMP is
# allowed as the pairwise cipher, group cipher will also be CCMP. Otherwise,
# TKIP will be used as the group cipher.
# (dot11RSNAConfigPairwiseCiphersTable)
# Pairwise cipher for WPA (v1) (default: TKIP)
#wpa_pairwise=TKIP CCMP
# Pairwise cipher for RSN/WPA2 (default: use wpa_pairwise value)
#rsn_pairwise=CCMP
# Time interval for rekeying GTK (broadcast/multicast encryption keys) in
# seconds. (dot11RSNAConfigGroupRekeyTime)
wpa_group_rekey=0
# Rekey GTK when any STA that possesses the current GTK is leaving the BSS.
# (dot11RSNAConfigGroupRekeyStrict)
#wpa_strict_rekey=1
# Time interval for rekeying GMK (master key used internally to generate GTKs
# (in seconds).
wpa_gmk_rekey=0
# Maximum lifetime for PTK in seconds. This can be used to enforce rekeying of
# PTK to mitigate some attacks against TKIP deficiencies.
wpa_ptk_rekey=0
# Enable IEEE 802.11i/RSN/WPA2 pre-authentication. This is used to speed up
# roaming be pre-authenticating IEEE 802.1X/EAP part of the full RSN
# authentication and key handshake before actually associating with a new AP.
# (dot11RSNAPreauthenticationEnabled)
#rsn_preauth=1
#
# Space separated list of interfaces from which pre-authentication frames are
# accepted (e.g., 'eth0' or 'eth0 wlan0wds0'. This list should include all
# interface that are used for connections to other APs. This could include
# wired interfaces and WDS links. The normal wireless data interface towards
# associated stations (e.g., wlan0) should not be added, since
# pre-authentication is only used with APs other than the currently associated
# one.
#rsn_preauth_interfaces=eth0

# peerkey: Whether PeerKey negotiation for direct links (IEEE 802.11e) is
# allowed. This is only used with RSN/WPA2.
# 0 = disabled (default)
# 1 = enabled
#peerkey=1

# ieee80211w: Whether management frame protection (MFP) is enabled
# 0 = disabled (default)
# 1 = optional
# 2 = required
#ieee80211w=0

# Association SA Query maximum timeout (in TU = 1.024 ms; for MFP)
# (maximum time to wait for a SA Query response)
# dot11AssociationSAQueryMaximumTimeout, 1...4294967295
#assoc_sa_query_max_timeout=1000

# Association SA Query retry timeout (in TU = 1.024 ms; for MFP)
# (time between two subsequent SA Query requests)
# dot11AssociationSAQueryRetryTimeout, 1...4294967295
#assoc_sa_query_retry_timeout=201

# disable_pmksa_caching: Disable PMKSA caching
# This parameter can be used to disable caching of PMKSA created through EAP
# authentication. RSN preauthentication may still end up using PMKSA caching if
# it is enabled (rsn_preauth=1).
# 0 = PMKSA caching enabled (default)
# 1 = PMKSA caching disabled
#disable_pmksa_caching=0

# okc: Opportunistic Key Caching (aka Proactive Key Caching)
# Allow PMK cache to be shared opportunistically among configured interfaces
# and BSSes (i.e., all configurations within a single hostapd process).
# 0 = disabled (default)
# 1 = enabled
#okc=1
##### Neighbor table ##########################################################
# Maximum number of entries kept in AP table (either for neigbor table or for
# detecting Overlapping Legacy BSS Condition). The oldest entry will be
# removed when adding a new entry that would make the list grow over this
# limit. Note! WFA certification for IEEE 802.11g requires that OLBC is
# enabled, so this field should not be set to 0 when using IEEE 802.11g.
# default: 255
ap_table_max_size=255
# Number of seconds of no frames received after which entries may be deleted
# from the AP table. Since passive scanning is not usually performed frequently
# this should not be set to very small value. In addition, there is no
# guarantee that every scan cycle will receive beacon frames from the
# neighboring APs.
# default: 60
ap_table_expiration_time=60
##### Wi-Fi Protected Setup (WPS) #############################################
# WPS state
# 0 = WPS disabled (default)
# 1 = WPS enabled, not configured
# 2 = WPS enabled, configured
wps_state=2
# AP can be configured into a locked state where new WPS Registrar are not
# accepted, but previously authorized Registrars (including the internal one)
# can continue to add new Enrollees.
ap_setup_locked=1
# Universally Unique IDentifier (UUID; see RFC 4122) of the device
# This value is used as the UUID for the internal WPS Registrar. If the AP
# is also using UPnP, this value should be set to the device's UPnP UUID.
# If not configured, UUID will be generated based on the local MAC address.
uuid=12345678-9abc-def0-1234-56789abcdef0
# Note: If wpa_psk_file is set, WPS is used to generate random, per-device PSKs
# that will be appended to the wpa_psk_file. If wpa_psk_file is not set, the
# default PSK (wpa_psk/wpa_passphrase) will be delivered to Enrollees. Use of
# per-device PSKs is recommended as the more secure option (i.e., make sure to
# set wpa_psk_file when using WPS with WPA-PSK).

# When an Enrollee requests access to the network with PIN method, the Enrollee
# PIN will need to be entered for the Registrar. PIN request notifications are
# sent to hostapd ctrl_iface monitor. In addition, they can be written to a
# text file that could be used, e.g., to populate the AP administration UI with
# pending PIN requests. If the following variable is set, the PIN requests will
# be written to the configured file.
#wps_pin_requests=/var/run/hostapd_wps_pin_requests
# Device Name
# User-friendly description of device; up to 32 octets encoded in UTF-8
device_name=Sitara
# Manufacturer
# The manufacturer of the device (up to 64 ASCII characters)
manufacturer=TexasInstruments
# Model Name
# Model of the device (up to 32 ASCII characters)
model_name=TI_Connectivity_module
# Model Number
# Additional device description (up to 32 ASCII characters)
model_number=wl18xx
# Serial Number
# Serial number of the device (up to 32 characters)
serial_number=12345
# Primary Device Type
# Used format: <categ>-<OUI>-<subcateg>
# categ = Category as an integer value
# OUI = OUI and type octet as a 4-octet hex-encoded value; 0050F204 for
#       default WPS OUI
# subcateg = OUI-specific Sub Category as an integer value
# Examples:
#   1-0050F204-1 (Computer / PC)
#   1-0050F204-2 (Computer / Server)
#   5-0050F204-1 (Storage / NAS)
#   6-0050F204-1 (Network Infrastructure / AP)
device_type=0-00000000-0
# OS Version
# 4-octet operating system version number (hex string)
#os_version=01020300

# Config Methods
# List of the supported configuration methods
# Available methods: usba ethernet label display ext_nfc_token int_nfc_token
#	nfc_interface push_button keypad virtual_display physical_display
#	virtual_push_button physical_push_button
config_methods=virtual_display virtual_push_button keypad
# WPS capability discovery workaround for PBC with Windows 7
# Windows 7 uses incorrect way of figuring out AP's WPS capabilities by acting
# as a Registrar and using M1 from the AP. The config methods attribute in that
# message is supposed to indicate only the configuration method supported by
# the AP in Enrollee role, i.e., to add an external Registrar. For that case,
# PBC shall not be used and as such, the PushButton config method is removed
# from M1 by default. If pbc_in_m1=1 is included in the configuration file,
# the PushButton config method is left in M1 (if included in config_methods
# parameter) to allow Windows 7 to use PBC instead of PIN (e.g., from a label
# in the AP).
#pbc_in_m1=1

# Static access point PIN for initial configuration and adding Registrars
# If not set, hostapd will not allow external WPS Registrars to control the
# access point. The AP PIN can also be set at runtime with hostapd_cli
# wps_ap_pin command. Use of temporary (enabled by user action) and random
# AP PIN is much more secure than configuring a static AP PIN here. As such,
# use of the ap_pin parameter is not recommended if the AP device has means for
# displaying a random PIN.
#ap_pin=12345670

# Skip building of automatic WPS credential
# This can be used to allow the automatically generated Credential attribute to
# be replaced with pre-configured Credential(s).
#skip_cred_build=1

# Additional Credential attribute(s)
# This option can be used to add pre-configured Credential attributes into M8
# message when acting as a Registrar. If skip_cred_build=1, this data will also
# be able to override the Credential attribute that would have otherwise been
# automatically generated based on network configuration. This configuration
# option points to an external file that much contain the WPS Credential
# attribute(s) as binary data.
#extra_cred=hostapd.cred