LAN issues
Issue 3.4.1 June 2005
287
Trunk configuration
A trunk port on an Ethernet switch is one that is capable of forwarding Ethernet frames on
multiple VLANs through the mechanism of VLAN tagging. IEEE 802.1Q specifies the standard
method for VLAN tagging. Cisco also uses a proprietary method called ISL. Avaya products do
not interoperate with ISL.
A trunk link is a connection between two devices across trunk ports. This connection can be
between a router and a switch, between two switches, or between a switch and an IP
Telephone. Some form of trunking or forwarding multiple VLANs must be enabled to permit the
IP Telephone and the attached personal computer to appear on separate VLANs. The
commands in
Table 69
enable trunking.
Note that Cisco can remove VLANs from a trunk port. This is a highly desirable feature because
only two VLANs at most should appear on a trunk port that is connected to an IP Telephone.
That is, broadcasts from nonessential VLANs should not be permitted to bog down the link to
the IP Telephone. The pre-3.2 version of P330 code did not have the capability to clear off
unwanted VLANs. Enabling 802.1Q trunking enabled all the VLANs. Newer versions of P330
code can limit the VLANs on a trunk, but in doing so they alter the previous trunking behavior.
VLAN binding feature (P330 v3.2.8)
With both Cisco and the pre-3.2 P330 code, the default behavior of trunking is to permit all
VLANs. With the new P330 code, the default behavior is to permit only the port VLAN or the
native VLAN, and to block all other VLANs. Additional VLANs are added to a port using the
VLAN binding feature. In addition, the port does not need to be a trunk at all to forward multiple
VLANs. For one application, connecting to an Avaya IP Telephone, the port must not be a trunk
(do not issue the set trunk command).
Table 69: Administration commands for VLAN trunking
Avaya P33xT v3.2.8 and later
Cisco CatOS
set trunk <mod/port> dot1q
By default, only the port VLAN or
the native VLAN is enabled on the
trunk port. Another set of
commands is required to specify
other allowed VLANs.
set trunk <mod/port> nonegotiate dot1q
By default, all VLANs (1 to1005) are enabled
on the trunk port. VLANs can be selectively
removed with the command clear trunk
<mod/port> <vid>.
Summary of Contents for Application Solutions
Page 1: ...Avaya Application Solutions IP Telephony Deployment Guide 555 245 600 Issue 3 4 1 June 2005 ...
Page 20: ...About This Book 20 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 21: ...Issue 3 4 1 June 2005 21 Section 1 Avaya Application Solutions product guide ...
Page 22: ...22 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 106: ...Call processing 106 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 124: ...Avaya LAN switching products 124 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 139: ...Issue 3 4 1 June 2005 139 Section 2 Deploying IP Telephony ...
Page 140: ...140 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 186: ...Traffic engineering 186 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 204: ...Security 204 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 228: ...Avaya Integrated Management 228 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 274: ...Reliability and Recovery 274 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 275: ...Issue 3 4 1 June 2005 275 Section 3 Getting the IP network ready for telephony ...
Page 276: ...276 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 356: ...Network recovery 356 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 366: ...Network assessment offer 366 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 367: ...Issue 3 4 1 June 2005 367 Appendixes ...
Page 368: ...Appendixes 368 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 394: ...Access list 394 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 414: ...DHCP TFTP 414 Avaya Application Solutions IP Telephony Deployment Guide ...