Other Installation Options: VPN Remote Phones
3.2 VLAN and IP Phones
This section describes the configuration of an VLAN networking infrastructure for use with Avaya IP Office and 4600 Series IP Phones. In this example an HP Procurve Ethernet 2626 PWR Ethernet switch is used to manage the VLAN’s. A basic understanding of the IEEE 802.2p/q standard is required.
The use of VLAN allows separate collision domains to be created on Ethernet switches. In the case of IP Office and IP Phones the advantages are:
1.It allows PC’s to continue in the same IP subnet while IP Phones can use a new and separate IP addressing scheme.
2.Broadcast traffic is not propagated between the PC data network and the IP Phones voice network. This helps performance as otherwise broadcast traffic must be evaluated by all receivers.
3.VLAN networking and traffic prioritisation at layer 2 are closely bound together in the same 802.2 standard. It is therefore easier to maintain L2 QOS when using a VLAN.
The table below shows the three ways in which VLAN can be deployed with an Ethernet Switch. The first two methods require only elementary configuration and as this document assumes both PC and IP Phones share the same Ethernet port, the focus will be the third method (overlapping).
Type | Description | Advantages | Disadvantages |
|
|
|
|
No VLAN | Both Voice and Data occupy the | Simple configuration | PC broadcast traffic adverse effect on |
| same collision domain |
| Voice traffic. |
|
|
| Requires two ports per user (one for IP |
|
|
| Phone and one for PC). |
|
|
|
|
Physical VLAN | Separate VLAN for data and voice | Simple configuration | Requires two ports on switch (one for |
|
|
| IP phone and one for PC. |
|
|
|
|
Overlapping | A single port on the switch | Requires only a single port | Complex configuration. |
VLAN | carrying both the IP Phones as | for both PC and IP Phone. |
|
| well as the PC traffic. | PC broadcast traffic cannot |
|
|
| adversely effect Voice |
|
|
| traffic. |
|
|
|
|
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H323 Install | Page 43 |
IP Office 4.2 |