Ajax has completed its IP telephony rollout. The legacy PBX has been removed, and the entire phone system is now on IP using Cisco Unified Communications Manager for call processing control.
Ajax has recently acquired Best Auto Accessories in Redmond, WA. Best is a small distributor of automobile parts and accessories. Best has 36 office employees and 48 warehouse workers in a single building. The Best phone system consists of a four-year-old key system. All calls enter the company through the company operator who then uses the overhead paging system to inform users of incoming calls.
Ajax plans to integrate Best as a remote site into the new Cisco IP telephony system at Ajax. The 36 office employees will be converted to IP phones with DID along with two phones in the warehouse that will not be DID. All IP phones will register with the Cisco Unified Communications Manager cluster at the Ajax central campus.
Ajax plans to connect with Best via a point-to-point circuit. The Redmond office will maintain external connections to the PSTN but will use the connection with Ajax to carry internal calls and for Internet connectivity. Internal calls crossing the WAN will use a G.729 codec with 20ms payload for bandwidth savings. Call Admission Control will be implemented using locations. The voice-mail system only supports the G.711 codec and will be centralized with the Cisco Unified Communications Manager.
When you analyze the distribution of the packet sizes that will be traversing the WAN link to the home office, you note that there is a potential for delay where voice packets could be trapped behind large data packets. Ajax wants you to determine if a 384 kbps WAN circuit is feasible. What is the recommended packet fragmentation size for this circuit?
A.
48 bytes
B.
100 bytes
C.
288 bytes
D.
320 bytes
E.
480 bytes