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MSS. MSS. MSS. MSS. Fixed Network. 1. 6. 2. i. 5. 3. 4. New Call Arrival. is the estimated load le > accepted load la. Y. Compute fr = la/le. N. Generate Probability Pr. Is Pr <= fr. Is a channel available. Y. N. Call Blocked. Y. N. Channel Assigned. Call Blocked.
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MSS MSS MSS MSS Fixed Network
1 6 2 i 5 3 4
New Call Arrival is the estimated load le > accepted load la Y Compute fr = la/le N Generate Probability Pr Is Pr <= fr Is a channel available Y N Call Blocked Y N Channel Assigned Call Blocked Ongoing Call Channel Release
G Handoff Region F D H E Segments EF,FG and FH are handoff – probable segments MT1 MT2 C B I J A
Flow A Flow A Flow B bandwidth bandwidth Flow B Time Time (b) (a)
IP Backbone UMTS CORE GGSN SGSN APC RNC AP AP Node- B AP AP AP UTRAN Mobile Node Mobile Node WLAN terminal Cell Phone (a) (b)
A call request arrival Voice call ? No (it’s a data call) yes New Call? No (it’s a handoff call) Try Cellular From cellular To WLAN ? yes No No free bandwidth avail For voice in cellular In double coverage? No No Try Cellular yes yes yes New Call ? Bandwidth Avail In WLAN? No Try WLAN yes In double coverage? yes No No Bandwidth Avail In Cellular ? No yes Bandwidth avail In WLAN? Try WLAN yes No yes No free bandwidth Avail in WLAN? No Rejected Accepted to Cellular yes Remain in Cellular Accepted to WLAN Accepted to Cellular Rejected
Low Losses Guaranteed Bit-rate Traffic Class Applications Delay Jitter Conversational (Real Time) Voice, one to one video Stringent Stringent Yes Streaming (Real Time) Broadcast Audio Video Constrained Constrained Yes Interactive (Best Effort) Web, Database, Games Loose Yes Background (Best Effort) Emails, File Transfer Yes
Conversational class conversational RT Streaming class streaming RT Interactive class Interactive best effort Background Background best effort Traffic class • Destination is not expecting the data within a certain time Fundamental characteristics • Preserve time relation (variation) between information entities of the stream • Preserve time relation (variation) between information entities of the stream • Request response • pattern • Preserve payload • content • Preserve payload • content • Conversational pattern (stringent and low delay) Example of the application - voice - streaming video - Web browsing - Background download of emails
CAC GGSN PPM MMM SGSN SGSN Core networks Access networks Monitor RNC RNC RNC Node B Node B AP Node B Roaming In Roaming out
UMTS domain WLAN domain WLAN domain WLAN domain Cdma2000 domain Other domains (Ethernet, ad hoc, Networks, sensor networks, WMANs, etc.) DiffServ Internet backbone GSM/GPRS domain WLAN domain Gateway Router Cellular Domain WLAN domain