RAD Data comm Vmux-2100 Voice Trunking Gateway Ethernet Main Link, E1/T1 Main Link, Vlan Support

Vmux-2100Installation and Operation Manual Chapter 1 Introduction

VLAN Support

Vmux-2100 supports VLAN, according to IEEE 802.1p&q. When VLAN support is enabled Vmux-2100 adds four bytes to the MAC layer of the Ethernet frame. The content of these bytes, MAC layer priority and VLAN ID, can be set by the user. In this mode, only VLAN format frames are sent and received by Vmux-2100. The following figure describes the VLAN tag format.

81 00

802.1D Tag Protocol Type

(802.1QTagType)

user_priority		0				VID
		CFI =
8	6	5	4	1	8	1
	Priority					VLAN ID

Figure 1-8. VLAN Tag Format

UDP Support

Table 1-2. UDP Source Port as Destination Voice Port

Field Length (Bits)	Field Description	Value
2 bytes	UDP Source Port*	2 – 497d
2 bytes	UDP Destination Port	2142d

* – The MSB of this field can be either 1 or 0 for inband end-to-end proprietary signaling.

Note The UDP Source Port field is used for destination voice bundle indication. For example, if the destination is:

Bundle 1 – 02, Bundle 2 – 03, Bundle 3 – 04, Bundle 4 – 05, etc.

For more information about VLAN tagging, see IEEE Std 802.1 p&q.

Ethernet Main Link

10/100BaseT main link receives Ethernet frames from the voice modules via the Ethernet switch and forwards them to the remote device over the IP network. The 10/100BaseT main link of Vmux-2100 supports full duplex transmission with autonegotiation and half duplex with the backpressure option.

E1/T1 Main Link

When using E1/T1 main link, Vmux-2100 adds HDLC flags to the Ethernet frames and transmits them over a TDM network. The E1/T1 main link interface of Vmux-2100 is fully redundant. When both of links are configured as active, Vmux-2100 starts sending data over the one that was connected first. If a loss of synchronization is detected on an active link, Vmux-2100 automatically switches to the backup link.

The E1/T1 links operate with loopback timing by deriving clock from the device connected to its E1/T1 port or with internal clock provided by the Vmux-2100 internal oscillator.

Functional Description 1-9