Mitel SX 200 IP NODE Instructions Guide

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•  Ports should be configurable to accept untagged information, pass this on to a specified VLAN, as well as accepting
tagged information. The port should also strip off tagging for data from a specific VLAN, but not strip data from other
VLANs. This is used when connecting the dual port phones and PCs to the network.
Some other VLAN guidelines for use with voice include:
•  Additional bandwidth is always good!
•  Use full duplex wherever possible
•  Don’t use VLAN 0
•  Set Priority to value 6 for...

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Actions->   Back     Add     Edit     Delete     Help
Port    DEFAULT_VLAN  voice_vlan    data_vlan     test4
----- + ------------  ------------  ------------  ------------
  1   | Untagged      Tagged        No            No
  2   | Untagged      Tagged        No            No
  3   | Untagged      Tagged        No            No
  4   | Untagged      Tagged        No            No
  5   | Tagged        Tagged        Tagged        No
  6   | No            No            No            Untagged
  7   |...

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With a Layer 3 device, such as a router, the packet per second (PPS) throughput is also important. With an IP-Phone the
frame rate is every 20ms. This means that the phone will send 50 packets per second and will also receive 50 packets per
second. Beware though how vendors might specify the PPS rating. For example, with two phones connected to a router
each port will send and receive 50PPS. That’s 100PPS per port, requiring that 200PPS to be handled. However, between
the phones only 50PPS went one...

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In the diagram, the network switch ports connected to the Dual Port Phones must be able to accept both untagged
information and tagged information. The untagged data will then be translated to a ‘data’ VLAN (1), whereas the voice will
be destined for a Voice VLAN (2). In the outgoing direction, these ports must also pass information from the Voice VLAN
still tagged, but traffic from the ‘data’ VLAN must be sent untagged for the devices that are incapable of handling VLAN
information.
The requirement...

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and device. In this instance, the loading on the network is almost back to that of a shared environment. The Layer 2
devices maintain a list of addresses and port location in internal memory. If the list is small, then the level of broadcasts
can also increase since new information is rapidly ‘aged’ out of the list.
Hence a large flat network can potentially grind to halt, not because of genuine traffic loading, but simply due to the
amount of broadcast traffic that will be needed. Using subnets helps...

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CalculationFormulaResult
Remote Phones10Total CCS at remote site Remote phones x 6CCS 60CCSPercentage trunk traffic Total CCS x 65% 39CCSPercentage intercom traffic Total CCS x (100 – trunk traffic)% 21CCS
Total traffic over WANTotal traffic – local traffic60.0CCS
Thus:
•  The total traffic handled is 60CCS.
From an earlier calculation it was highlighted that a T1 WAN link, without QoS, could handle 6 G.711 ‘voice channels’.
From ErlangB tables with P.001 blocking such a link can handle 41.1CCS. There...

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each the other two nodes. Obviously in the second scenario less bandwidth will be needed per node to and from a
particular node, but the total per node will remain about the same, i.e. 7.5% + 7.5% = 15%.
4.3.1  IP Trunk Limit working example
Consider the following example:
•  Two equal sized systems
•  Exclusively 120 IP Trunks/phones
•  Calls from TDM, or to TDM devices including trunks, use G.711 CODEC
•  Calls between IP devices use the G.729 CODEC
•  Traffic is typically 35% internal, the...

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*1 Note: The number of channels needed purely for internal traffic is 7. For external traffic the total number is 10.
However, together the total is only 13. How is this so? The reason is that a number of channels will have shared use, in
this case it must be 4 (10+7-13). The higher G.711 rate is used to ensure adequate bandwidth at all times.
*2 Note: The bandwidths of 100k and 40k are used assuming that Ethernet is used between the two nodes. For example if
PPP were used between the two nodes then...

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5. Getting Started
The above two sections have dealt with network conditions and call traffic. However, before any of this can occur, the
system needs to be installed and the end devices need some code to get them running.
5.1  Start-up sequence for phones:
This is the normal sequence of events for a dual port IP Phone, where VLANs are implemented:• Power up•  Run ‘Boot’ code•  Request IP address (untagged) through DHCP•  Receive IP address from default VLAN (data VLAN) and specific phone and system...

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5.4  DHCP Lease Time
To allow users to move off the local sub-net, or to let new people join a subnet, a method is needed to give up an IP
address and also obtain a new address. If a phone is disconnected it obviously cannot talk to the DHCP server, so
another method is needed to free up unused addresses. This is the DHCP lease time. This helps provide the Dynamic in
DHCP by clearing out unused IP addresses and making them available for new requests.
The timer can be set from a few minutes to weeks....