6LoWPAN 在设计 IPv6 header 压缩主要是将 IPv6 headers 之间的共同值省略或是可以由 layer 2 header 取得数据而省略. 下列哪些叙述是正确的 ？A.version 欄位可省略, 因为都是 IPv6#B.Payload length 欄位可以省略, 因为可以由 Layer 2 header 计算得知#C.Source/Destination IPv6 address 欄位无法省略, 因为封包一定要有 IPv6 网址#D.如果是 Link-local IPv6 address 就可以省略, 因为 IPv6 网址的Interface ID 可以由 layer 2 MAC address 取得
6LoWPAN 在设计 IPv6 header 压缩主要是将 IPv6 headers 之间的共同值省略或是可以由 layer 2 header 取得数据而省略. 下列哪些叙述是正确的 ？
A.version 欄位可省略, 因为都是 IPv6#B.Payload length 欄位可以省略, 因为可以由 Layer 2 header 计算得知#C.Source/Destination IPv6 address 欄位无法省略, 因为封包一定要有 IPv6 网址#D.如果是 Link-local IPv6 address 就可以省略, 因为 IPv6 网址的Interface ID 可以由 layer 2 MAC address 取得参考答案和解析
version 欄位 可省略 , 因为都是 IPv6;Payload length 欄位 可以省略 , 因为可以由 Layer 2 header 计算得知;如果是 Link-local IPv6 address 就可以省略 , 因为 IPv6 网址的 Interface ID 可以由 layer 2 MAC address 取得
相关考题：
Which two are valid fields in an IPv6 header?() A. Hop LimitB. Next HeaderC. Fragment OffsetD. Header Checksum
In a Bridged 1483 network, what Layer 2 encapsulations are passed between the DSL bridge and the ERX?() A. single ATM headerB. single Ethernet headerC. ATM header followed by a PPP headerD. ATM header followed by an Ethernet header
An IPv6 host is configured to request a specific path through the network to reach a destination.Which IPv6 extension header should be used?() A. RoutingB. Hop-by-HopC. FragmentationD. Destination Options
What are three benefits of using IPv6?() A. IPv6 supports a greater level of security by integrating features that were optional add-ons in IPv4.B. IPv6 reduces administrative overhead using stateless address autoconfiguration for hosts.C. IPv6 eliminates the need for private to public NAT using a large address pool.D. IPv6 provides backward compatibility with IPv4 using the Next Header field.E. IPv6 represents large IP addresses using dotted decimal notation.
Why is IPv6 packet processing more effective than IPv4 packet processing?() A. fixed header sizeB. smaller header sizeC. fewer header fieldsD. variable header size
以下关于IPv6地址类型的描述正确的是( )。①IPv6地址是被IETF设计用来替代IPv4的下一代IP协议。②IPv6地址中::只能出现一次。③IPv6地址的长度为128bit，通常写作8组，每组用4个十六进制数表示，每组开头的十六进制数如果是0则可以省略。④IPv6地址可以分为单播地址、广播地址、任意播地址和组播地址。A.①②B.①②③C.①②④D.①②③④
改变MS功率的命令和改变TA的命令在每一个下行的SACCH信息块所带的（）传送给MS。A、第一层的报头（Layer 1 Header）B、第二层的报头（Layer 2 Header）C、第三层的报头（Layer 3 Header）D、第四层的报头（Layer 4 Header）
What are three benefits of using IPv6?（）A、IPv6 supports a greater level of security by integrating features that were optional add-ons in IPv4.B、IPv6 reduces administrative overhead using stateless address autoconfiguration for hosts.C、IPv6 eliminates the need for private to public NAT using a large address pool.D、IPv6 provides backward compatibility with IPv4 using the Next Header field.E、IPv6 represents large IP addresses using dotted decimal notation.
Which two are valid fields in an IPv6 header?（）A、Hop LimitB、Next HeaderC、Fragment OffsetD、Header Checksum
在关于“省略”这一叙述速度的论述中，正确的是（）A、文本中不容许有任何词语来表述被省略的时间B、被省略的事件毫无意义C、省略可以突出事件之间的逻辑关联D、被省略的事件与没被省略的事件之间没有关联
Which header or set of headers does CRTP compress？ （）A、Layer 2B、Layer 3C、Layer 4D、Layer 2 and Layer 3E、Layer 3 and Layer 4
Which statement is true concerning 6to4 tunneling?（）A、The edge routers can use any locally configured IPv6 address.B、Hosts and routers inside a 6to4 site will need a special code.C、An edge router must use IPv6 address of 2002::/16 in its prefix.D、IPv4 traffic is encapsulated with an IPv6 header.
Where is the MPLS label imposed？（）A、after the Layer 3 header and before the Layer 2 payloadB、after the Layer 3 header and before the Layer 4 payloadC、after the Layer 2 header and before the Layer 1 payloadD、after the Layer 1 header and before the Layer 2 payloadE、after the Layer 2 header and before the Layer 3 payload
Which three are characteristics of IPv6?（）A、An IPv6 address is 128 bits long.B、An IPv6 header contains the header checksum field.C、An IPv6 header is 20 bits long.D、An IPv6 header contains the next header field.E、IPv6 route rs send RA messages.F、An IPv6 header contains the protocol field.
During the IPv6 address resolution， a node sends a neighbor solicitation message in order to discover which of these？（）A、The Layer 2 multicast address of the destination nodeB、The solicited node multicast address of the destination nodeC、The Layer 2 address of the destination node based on the destination IPv6 addressD、The IPv6 address of the destination node based on the destination Layer 2 address
下列关于Teredor说法，错误的是（）。A、Teredor在主机间通过隧道传输IPV6数据包，解决了目前互联网边界和多层NAT配置6to4所面临的问题B、Teredor将IPV6数据封装成IPV4UDP报文，以穿越NAT.C、Teredor作为显示IPV6最后一种转换技术而设计D、Teredor是一项IPV6转换技术，仅够实现在处于单个PV4NAT后的主机之间的IPV6自动隧道。
单选题During the IPv6 address resolution， a node sends a neighbor solicitation message in order to discover which of these？（）AThe Layer 2 multicast address of the destination nodeBThe solicited node multicast address of the destination nodeCThe Layer 2 address of the destination node based on the destination IPv6 addressDThe IPv6 address of the destination node based on the destination Layer 2 address
单选题Which header or set of headers does CRTP compress？ （）ALayer 2BLayer 3CLayer 4DLayer 2 and Layer 3ELayer 3 and Layer 4
单选题在关于“省略”这一叙述速度的论述中，正确的是（）A文本中不容许有任何词语来表述被省略的时间B被省略的事件毫无意义C省略可以突出事件之间的逻辑关联D被省略的事件与没被省略的事件之间没有关联
单选题Why is IPv6 packet processing more effective than IPv4 packet processing?（）Afixed header sizeBsmaller header sizeCfewer header fieldsDvariable header size
单选题During the IPv6 address resolution， a node sends a neighbor solicitation message in order to discover which of these？ （）A The Layer 2 multicast address of the destination nodeB The solicited node multicast address of the destination nodeC The Layer 2 address of the destination node based on the destination IPv6 addressD The IPv6 address of the destination node based on the destination Layer 2 address
多选题Which three are characteristics of IPv6?（）AAn IPv6 address is 128 bits long.BAn IPv6 header contains the header checksum field.CAn IPv6 header is 20 bits long.DAn IPv6 header contains the next header field.EIPv6 route rs send RA messages.FAn IPv6 header contains the protocol field.
单选题An IPv6 host is configured to request a specific path through the network to reach a destination.Which IPv6 extension header should be used?（）ARoutingBHop-by-HopCFragmentationDDestination Options
单选题In a frame ，the MPLS label is imposed（）.AAfter the Layer3 header and before Layer2 headerBAfter the Layer2 header and before Layer3 headerCWithin the Layer 3 headerDBefore the layer 2 header
单选题Where is the MPLS label imposed？（）Aafter the Layer 3 header and before the Layer 2 payloadBafter the Layer 3 header and before the Layer 4 payloadCafter the Layer 2 header and before the Layer 1 payloadDafter the Layer 1 header and before the Layer 2 payloadEafter the Layer 2 header and before the Layer 3 payload
单选题In a Bridged 1483 network, what Layer 2 encapsulations are passed between the DSL bridge and the ERX?（）Asingle ATM headerBsingle Ethernet headerCATM header followed by a PPP headerDATM header followed by an Ethernet header
多选题Which two are valid fields in an IPv6 header?（）AHop LimitBNext HeaderCFragment OffsetDHeader Checksum