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What is trunk? What is difference between trunk and gateway?


Re: Trunk

ok u asking about two diffrent things


in switched network there is somthing called virtual LAN VLAN this vlan is ssparating client in L2 put each vlan in diffrent subnet and braodcast domain

if u have two or more switchs and u want to pass traffic beween same valns in diffrent switches u need a link called trunk that pass vlans through but dose not let them communicate togather they still saparate on L2


is the exist poit to hosts on a given network

also the term gateways u sed in voice network as it is a device perform protocol translation

if u have users in a network and want to sent traffic to internet or any IP that is not in the local LAN then the client will send it to the gateway and if the gateway has route to that IP will handel the routing

if u talk about trunk from VOIP side

trunk is a link to outside voice provider like sip trunk or a link to voice mail through maybe a sip tunk as will witch take a boundel of calls

gateway in VOIP handel call routing inbound calls outboundcalls and tranalte between PSTN tdm calls and VOIP packet calls

trunk can be terminate on a gateway then the trunk is feature can be configured in a VOIP gateways

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Re: Trunk

Everything Marwan said is correct, but let me state it in a diffrerent way to clarify.

Trunk: A trunk refers to any communication line that carries multiple 'channels'.

In the data (IP) world, a trunk connection carries multiple virtual LANs (VLANs). For example, in VoIP, a trunked IP link will often carry a Data VLAN and a Voice VLAN.

In the voice world, a trunk usually refers to a channelized T-1 or E-1 TDM (i.e. non-IP) connection. These are usually PSTN connection provided by the Telco or a connection to a TDM-based PBX. However, a voice trunk can also refer to a SIP trunk or an inter-cluster trunk. These are both IP-based trunks, and are therefore virtual, but otherwise act like TDM trunks.

Gateway: This can mean so many things that it doesn't mean anything out of context.

A data gateway is merely the next-hop address for IP data packets. It is what is configured on end devices that allow they to route packets outside the immeidate network.

A voice gateway (Often called a VG) is typically the point between traditional TDM, channel-based voice networks like the PSTN and newer packetized, IP-based voice networks. These devices are responsible for converting digital or analog channels into IP streams and converting IP streams into digital or analog channels. They also must understand and convey address information, such as Called number and Calling number between these networks.

Therefore, the short answer to your question is that a gateway is (typically) a physical device, whereas the trunk is (typically) a cable connection to another device.

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Re: Trunk

Apologies for uncompleted question. Yes, I am asking about Voip Trunk (h.225, intercluster trunk (gatekeeper/non-gatekeeper),SIP trunk) & VG.

If I am connecting two CM cluster via a trunk and another two CM cluster via voice gateway. What is a difference between them? Which solution is best?

thanks for your reply.

Re: Trunk

if u cnnect them via trunk called ICT in the route pattren u can add the ICT as the endpoint to toute the call to

and all the call control will be in the CM

while lets say u have h323 gateway in between u need to define the gateway in both CMs and route th call going to the other CM to the gateway on the gateway u need to have dial-peers to handel the calls

also u could make translation on the gateway or prefixing digits stripting digits and so on

also if u use the gateway as gatekeper u can make ICT gatekeeper control this way u can do CAC to control the number off calls that can pass between the two CMs at a time

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Re: Trunk


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