Cisco Systems IPMUX-1 Ethernet User Port, Internal Switch Operation Modes, Rate Limiter Option

Chapter 1 Introduction IPmux-1/1EInstallation and Operation Manual

Ethernet User Port

The Ethernet user port allows a user to aggregate both TDMoIP traffic and his private network LAN traffic to a single Ethernet network connection without requiring an access switch. This is a cost effective solution for MTU or small office applications. A rate limiter to restrict user port traffic is supported.

IPmux-1/1E contains an internal switch where one of its ports is connected to a TDMoIP interworking function, another external switch port is used as the user port, and the third is used as an Ethernet network port.

Ethernet User Port

E1 Port

Ethernet

Internal Network Port

Switch

TDMoIP

Figure 1-18. IPmux-1/1E with Ethernet User Port

Note Priority is always given to TDMoIP packets inside the internal switch.

Internal Switch Operation Modes

IPmux-1/1E offers a user LAN port in addition to the LAN port on the network side. The device performs switching at level 2. The switch supports both transparent bridging and VLAN-aware bridging. The switch supports rate limiting of traffic going from the user port to the network port. It supports up to 12K MAC addresses (depending on their values and the order in which they are learned).

The switch modes are described later in this section. They are:

•Basic mode

•User Tagged mode

•User Untagged mode

•Rate mode

•Rate + User Tagged mode.

•Rate + User Untagged mode

Rate Limiter Option

In this option a rate limiter is available to limit user port traffic. This feature is valuable when a limited bandwidth DSL modem, for example, is used to extend the Ethernet link (generally when the Ethernet link rate is limited/shaped to a lower rate after IPmux). In this case TDMoIP packets will be dropped in the modem even if it was prioritized at the IPmux internal switch. This is prevented by limiting the user port to actual link rate minus TDMoIP bandwidth. The rate limiter can limit user traffic at 50 kbps steps up to 5 Mbps and in 1 Mbps steps from 5 Mbps to 100 Mbps.

1-26 Functional Description