Cisco Systems 7920 IP manual VLANs

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VLANs

VLANs are used by WLAN networks to provide two distinct functions:

∙Segment traffic into distinct broadcast domains (IP subnets).

∙Create separate security domains for different security models (such as open, WEP, LEAP, Protected Extensible Authentication Protocol (PEAP), EAP Transport Layer Security (EAP/TLS))

The Cisco AVVID design guide states that separate VLANs should be created for voice and data traffic. This allows appropriate QoS to be provided to different classes of traffic as well as addressing issues such as IP addressing, security, and network dimensioning.

Cisco AP350, AP1100, and AP1200 support up to 16 VLANs. Cisco APs can be connected to Cisco Catalyst switches through 802.1q trunks (hybrid mode: native VLAN (Port VLAN ID (PVID)) is not tagged). Each VLAN is then mapped to a unique SSID on the AP. Users (or IP phones) can then be assigned to VLANs based on either static configuration of SSID or dynamically though the use of RADIUS authentication. Each VLAN can use a different security mechanism, although only one can be unencrypted (open). The following is an example of configuring VLANs on VxWorks−based APs (AP350 or AP1200):

The following is an example of configuring VLANs on Cisco IOS Software−based APs (AP1100 or AP1200):

Cisco − Wireless IPT Design Guide for the Cisco 7920 IP Phone

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Contents Table of Contents Requirements IntroductionPrerequisites RF Overview Site Surveys and Design Recommendations Cisco 7920 IP Phone OverviewWlan Overview Components UsedVoIP QoS Rssi∙ Delay Variation Jitter Not to exceed 30ms Security for the Cisco 7920 and Wlan Networks Number of 802.11b IP Phones per AP Network SizingNumber of 802.11b Devices per AP Page Numbers of 802.11b Phones per Layer 2 Subnet or Vlan Understanding Layer 2 and Layer 3 Roaming Understanding Roaming Terminology Layer 2 Roaming Page Layer 3 Roaming VLANs Wlan QoS for VoIP Page Page Page Interconnecting WLANs to Cisco Campus Infrastructure Connecting APs to the Catalyst 3550 SMI or EMI Connecting APs to the Catalyst 2950 EI Connecting APs to the Catalyst 2950 SICaveats and Limitations Other Caveats and Limitations Call Admission ControlDesigning Around the Lack of Layer 3 Roaming Related Information
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