802.1X Authentication Services Configuration Guide, Cisco IOS Release 15M&T - IEEE 802.1X Multidomain Authentication

Publisher

Cisco Systems

URL

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_usr_8021x/configuration/15-mt/sec-user-8021x-15-mt-book/sec-ieee-mda.html

Published

2012-11-29

Updated

unknown

Accessed

2026-10-02

HTTP status

200

License

Cisco documentation; all rights reserved; no-redistribution; short excerpts and locators only

Source notes citing this source

• In 802.1X multidomain mode, a port is error-disabled if more than one device tries to authorize in either the voice or the data domain. It is also error-disabled if, while unauthorized, it sees more than five devices on the data VLAN or more than one voice device on the voice VLAN. in context
• Under 802.1X multidomain authentication on Cisco IOS, if the AAA server does not send device-traffic-class=voice, the switch treats the voice device as a data device. in context
• Under Cisco IOS multidomain authentication, non-Cisco IP phones are allowed into both the data and voice VLANs. The data VLAN lets the phone reach a DHCP server to get an IP address and the voice VLAN information. in context
• With IEEE 802.1X multidomain authentication on Cisco IOS, a voice device is authorized only if the AAA server sends the Cisco AV pair device-traffic-class=voice. in context
• When the 802.1X host mode is multi-domain, a voice VLAN must be configured for the IP phone. Cisco recommends MDA rather than CDP bypass for IP phones on dot1x-secured ports. in context

Cite this source record

APA

WarmTransfer. (2012, November 29). 802.1X Authentication Services Configuration Guide, Cisco IOS Release 15M&T - IEEE 802.1X Multidomain Authentication. WarmTransfer. https://warmtransfer.net/knowledge/sources/cisco-ios-15mt-8021x-mda

BibTeX

@misc{warmtransfer-cisco-ios-15mt-8021x-mda,
  title  = {802.1X Authentication Services Configuration Guide, Cisco IOS Release 15M&T - IEEE 802.1X Multidomain Authentication},
  author = {{WarmTransfer}},
  year   = {2012},
  url    = {https://warmtransfer.net/knowledge/sources/cisco-ios-15mt-8021x-mda},
  note   = {Cisco Systems, accessed 2026-10-02}
}