Ace ACE-3205, Инструкция по установке и эксплуатации

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Installation and Operation Manual Chapter 6 Monitoring and Diagnostics
ACE-3105, ACE-3205 Ver. 5.2 Frequently Asked Questions 6-111
6.7 Frequently Asked Questions
Q Does ACE-3105, ACE-3205 support ATM over PSN and ATM switching at the
same time?
A Yes, both function types are supported by the unit and can be utilized
simultaneously.
Q What kinds of AAL types does ACE-3105, ACE-3205 support over a
packet-switched network?
A ACE-3105, ACE-3205 supports all AAL type (AAL1, AAL2, and AAL5) and
transfers them via the PSN transparently.
Q What exactly is the timeout mechanism?
A When using the ATM cell concatenation mechanism, ACE-3105, ACE-3205
stores the data cells until the maximum number of concentrated cells is
reached. TDM traffic, however, requires continuous delivery of data.
Accordingly, ACE-3105, ACE-3205 uses the timeout mechanism to reduce the
cell storage time before encapsulated data is sent towards the PSN. The
timeout delay value can be set between 100 to 5,000,000 microseconds. The
timer accuracy is +500 microseconds.
Q In packet-switched traffic, what triggers the sending of a packet?
A ACE-3105, ACE-3205 has several trigger of sending packet towards the PSN:
ƒ When reaching the maximum cells concatenation number
ƒ
When the timeout timer has expired
ƒ When the end of AAL5 (SDU bit=1, configurable) is received.
Q How can an ATM VPs (virtual paths) be mapped to a pseudowire?
A Any ATM VP can be mapped to a PW using 1:1 mode (1 VP per PW) or N:1
mode (N VPs per PW).
Figure 6-69
demonstrates how VPs can be mapped to pseudowires in the 1:1
encapsulation mode (for more information, refer to Appendix E ).