When to use a tech-prefix and when not to?

Unanswered Question
Oct 1st, 2008
User Badges:
  • Green, 3000 points or more

I have (3) GKs. I have everything working correctly. Each GK has it's Tech-Prefix or type-prefix.

Off of each GK I have a couple h323 GWs. They have Tech-Prefixes also to


gw-type-prefix 1#* default-technology


gw-type-prefix 2#* default-technology


gw-type-prefix 3#* default-technology


h323-gateway voip tech-prefix 1#

(this would then go GK-A)


h323-gateway voip tech-prefix 2#

(this would go to GK-B)


h323-gateway voip tech-prefix 3#

(This would go to GK-C)

Do I need to add the other tech-prefixs to each of the other GKs?


gw-type-prefix 1#* default-technology

gw-type-prefix 2#*

gw-type-prefix 3#*

I'm guess I only need to use tech-prefix when I have a h323 end point such as a GWY or CUCM cluster correct?

Thanks much!

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (1 ratings)
Marwan ALshawi Thu, 10/02/2008 - 04:30
User Badges:
  • Purple, 4500 points or more
  • Community Spotlight Award,

    Best Publication, December 2015

A technology prefix identifies H.323 endpoints by type or class or identifies a resource pool to the gatekeeper. It is important to configure a default technology prefix on the gatekeeper and a technology prefix on the gateway for everything to work correctly. Select a technology prefix to identify the type of gatewayin this case, a voice gatewayto the gatekeeper

Defining a technology prefix is important for proper operation because in most cases, calls do not route properly if this step is not done. Typically, the called number matches a zone prefix, not a registered E.164 address. In this case, if a technology prefix is not also matched, the call is rejected

if helpful Rate

Tommer Catlin Thu, 10/02/2008 - 07:55
User Badges:
  • Green, 3000 points or more

Thanks Marwan .

So are my configurations correct or did I go overboard on the prefixs?

Thanks much!

Marwan ALshawi Fri, 10/03/2008 - 05:38
User Badges:
  • Purple, 4500 points or more
  • Community Spotlight Award,

    Best Publication, December 2015

u can either leave to defualt and use the zone prefix to control the call transfere betwen GWs and GKs

or u could use gw-type-prefix as a area code for example for that zone or gateway instead of configuring zone prefix on the GK

for example

u wanna calls come to KA to start with 444 to be send to GWA

configure GWA to rigister with GKA and configure the gw-type-prefix like

h323-gateway voip tech-prefix 444

then check on the GK b useing

show gatekeeper zone status

show gatekeeper endpoints

Display the technology prefixes registered with the gatekeeper. Enter the show gatekeeper gw-type-prefix

if helpful Rate

Tommer Catlin Mon, 10/06/2008 - 09:50
User Badges:
  • Green, 3000 points or more

Thanks buddy!

Hey quick question, have you ever seen a phased migration of GWs to GKs work? I cant seem to figure out how a phased migration would work?! If my existing GWs are using Dial-Peers to/from other GWs, the only way I see of moving the GWs to the GKs is to do a flash cut. (move all GWs to the GK at once)


Claudio Quiroz ... Wed, 04/12/2017 - 08:30
User Badges:

Hi Marwan,

According your answer, Should tech-prefixs and full technology be used when you wouldn´t set the zone prefix on GK?

Shall I set all prefix in all Gatekeepers on the network (gw-type-prefix 1#*, 2#* and 3#*)?


This Discussion