私有报头，接入网络信息，包括网络的RAT、小区信息等。语法如下
P-Access-Network-Info = "P-Access-Network-Info"HCOLON
access-net-spec *(COMMA access-net-spec)
access-net-spec = (access-type / access-class) *(SEMI access-info)
access-type = "IEEE-802.11" / "IEEE-802.11a" / "IEEE-802.11b" / "IEEE-802.11g"/ "IEEE-802.11n" / "3GPP-GERAN" / "3GPP-UTRAN-FDD" /"3GPP-UTRAN-TDD" / "3GPP-E-UTRAN-FDD" / "3GPP-E-UTRAN-TDD" / "ADSL"/ "ADSL2" / "ADSL2+" / "RADSL" / "SDSL" / "HDSL" / "HDSL2" /"G.SHDSL" / "VDSL" / "IDSL" / "3GPP2-1X" / "3GPP2-1X-Femto" / "3GPP2-1X-HRPD" /"3GPP2-UMB" / "DOCSIS" / "IEEE-802.3" /"IEEE-802.3a"/ "IEEE-802.3e" / "IEEE-802.3i" /"IEEE-802.3j"/ "IEEE-802.3u" / "IEEE-802.3ab"/"IEEE-802.3ae"/ "IEEE-802.3ah" / "IEEE-802.3ak" /"IEEE-802.3aq"/ "IEEE-802.3an" / "IEEE-802.3y" /"IEEE-802.3z"/ GPON/ XGPON1 / "GSTN"/"DVB-RCS2"/token
access-class = "3GPP-GERAN" /"3GPP-UTRAN"/"3GPP-E-UTRAN"/ "3GPP-WLAN" / "3GPP-GAN" /"3GPP-HSPA" / "3GPP2" /token
np = "network-provided"
access-info = cgi-3gpp / utran-cell-id-3gpp / dsl-location / i-wlan-node-id/ ci-3gpp2/ ci-3gpp2-femto/eth-location / fiber-location / operator-specific-GI / np / gstn-location / local-time-zone / dvb-rcs2-node-id / utran-sai-3gpp / extension-access-info
extension-access-info = generic-param
cgi-3gpp = "cgi-3gpp" EQUAL (token / quoted-string)
utran-cell-id-3gpp = "utran-cell-id-3gpp" EQUAL (token / quoted-string)
i-wlan-node-id = "i-wlan-node-id" EQUAL (token / quoted-string)
dsl-location = "dsl-location" EQUAL (token / quoted-string)
eth-location = "eth-location" EQUAL (token / quoted-string)
fiber-location = "fiber-location" EQUAL (token / quoted-string)
ci-3gpp2 = "ci-3gpp2" EQUAL(token / quoted-string)
ci-3gpp2-femto = "ci-3gpp2-femto" EQUAL (token / quoted-string)
gstn-location ="gstn-location" EQUAL (token /quoted-string)
dvb-rcs2-node-id = "dvb-rcs2-node-id"EQUAL quoted-string
local-time-zone = "local-time-zone"EQUAL quoted-string
operator-specific-GI = "operator-specific-GI" EQUAL (token / quoted-string)
utran-sai-3gpp = "utran-sai-3gpp" EQUAL(token / quoted-string)
例如：
P-Access-Network-Info: 3GPP-E-UTRAN-TDD;utran-cell-id-3gpp=460005001DC2E302
