Multi-Tech Systems E1, MultiVOIPTM, MVP-2410, MVP-3010 manual 113

MultiVOIP User Guide Technical Configuration

H.323 Call Signaling Parameter Definitions

(cont’d)

Field Name	Values	Description
H.323 Version 4 Parameters
Parallel H.245	Values: Y/N
(FS + Tun)	Description:	FS (Fast Start or Fast Connect) is
	a Q.931 feature of H.323v2 to hasten call
	setup as well as ‘pre-opening’ the media
	channel before the CONNECT message is
	sent. This pre-opening is a requirement for
	certain billing activities. Under Parallel
	H.245 FS + Tun, this Fast Connect feature can
	operate simultaneously with H.245
	Tunneling (see description above).
Annex –E (AE)	Values: Y/N
	Description: Multiplexed UDP call signaling
	transport. Annex E is helpful for high-
	volume voip system endpoints. Gateways
	with lesser volume can afford to use TCP to
	establish calls. However, for larger volume
	endpoints, the call setup times and system
	resource usage under TCP can become
	problematic. Annex E allows endpoints to
	perform call-signaling functions under the
	UDP protocol, which involves substantially
	streamlined overhead. (This feature should
	not be used on the public Internet because of
	potential problems with security and
	bandwidth usage.)

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