• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.71-76
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• 2005

The 070-VOIP service were began to support system of E.164 and an IP address service. The address system was proposed how an convergence of E.164 address system was worked with an EPC and an IP address to the multimedia convergence service within the integration of wireless and wireline. In future, it was presented the way that the end user could use an integrated address system to be based on E.164 in BcN networks. An expansibility will be easy to all things are put into in knowledge that u- address system use an integrated address system to the basis of E.164 system.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.243-248
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• 2012

In this paper we simulate the capacity of VOIP calls through WiFi network by computer simulations using OPNET modeler. The results show that sudden quality degradations occur on all VoIP calls when the number of call of an AP(Access Point) increases beyond a specific value. The reason of the quality degradation was turned out to be the queueing delay at the down link of AP. Under the IEEE 802.11b environments, the maximum number of VoIP calls of an AP maintaining the required voice quality (MOS > 2.5), was evaluated as 5, 12, and 27 when we use G.711, G.729a, and G.729a VAD codec, respectively.