User`s manual

SIP User's Manual 9. Networking Capabilities
Version 5.0 237 October 2006
9.10 VLANS and Multiple IPs
9.10.1 Multiple IPs
Media, Control, and Management (OAM) traffic in the gateway can be assigned one of the
following IP addressing schemes:
 Single IP address for all traffic (i.e., Media, Control, and OAM).
 Separate IP address for each traffic type.
For separate IP addresses, the different traffic types are separated into three
dedicated networks. Instead of a single IP address, the gateway is assigned three IP
addresses and subnet masks, each relating to a different traffic type. This architecture
enables users to integrate the gateway into a three-network environment that is
focused on security and segregation. Each entity in the gateway (e.g., Web and RTP)
is mapped to a single traffic type (according to Table 9-1 on page 238) in which it
operates.
 Two separate IP addresses (Dual IP mode)--one for a specific traffic type and the
other for a combination of two traffic types.
In Dual IP mode, the gateway is assigned two IP addresses for the different traffic
types. One IP address is assigned to a combination of two traffic types (Media and
Control, OAM and Control, or OAM and Media), while the other IP address is assigned
to whichever traffic type that is not included in this combination. For example, a typical
scenario using this mode would include one IP address assigned for Control and
OAM, and another IP address assigned for Media.
Notes:
•
A
default gateway is supported only for the Media traffic type; for the
other two, use the IP Routing table.
• The IP address and subnet mask used in the Single IP Network
mode are carried over to the OAM traffic type in the Multiple IP
Network mode.
For detailed information on integrating the gateway into a VLAN and multiple IPs network,
refer to Section
9.10.3 on page 239. For detailed information on configuring the multiple IP
parameters, refer to Table
6-1 on page 130.
9.10.2 IEEE 802.1p/Q (VLANs and Priority)
The Virtual Local Area Network (VLAN) mechanism enables the gateway to be integrated
into a VLAN-aware environment that includes switches, routers and endpoints.
When in VLAN-enabled mode, each packet is tagged with values that specify its priority
(class-of-service) (IEEE 802.1p) and the identifier (traffic type) of the VLAN to which it
belongs (media, control or management) (IEEE 802.1Q).
The class-of-service mechanism can be utilized to accomplish Ethernet QoS. Packets sent
by the gateway to the Ethernet network are divided into five, different-priority classes
(Network, Premium media, Premium control, Gold and Bronze). The priority of each class
is determined by a corresponding ini file parameter.
Traffic type tagging can be used to implement Layer 2 VLAN security. By discriminating
traffic into separate and independent domains, the information is preserved within the
VLAN. Incoming packets received from an incorrect VLAN are discarded.