多项选择题
A.A voice packet is sent via multiple fixed-length cells; a portion of the last cell is padding, requiring more bandwidth.
B.ADSL typically uses PPPoE encapsulation, which adds additional overhead to each voice packet.
C.A voice packet is sent via multiple fixed-length cells; each cell has about 10% Layer-2 header overhead.
D.IPSec requires additional overhead for the header and hash.
E.ADSL carrier band requires additional bits to be carried over the wire to the DSL Access Concentrator.
单项选择题 Refer to the exhibit. With an IPSec tunnel established between remote Router A and head-end router B, how can the Service Provider Edge Router identify Voice over IP packets flowing through the IPSec tunnel from a Cisco 7960 IP phone?（）
单项选择题 Refer to the exhibit. An enterprises security policy disallows the use of wireless on a Teleworker PC. Choose the most appropriate 830 security feature to use to enforce the security policy.（）
单项选择题 Refer to the exhibit. Available public Internet sites are sometimes used for estimating performance. Which statement regarding their use for estimating VPN performance is correct?（）