tailieunhanh - windows server 2008 tcp ip protocols and services microsoft 2008 phần 9

Giải quyết địa chỉ tên, còn được gọi là phân giải tên đảo ngược xảy ra khi một khách hàng DNS hoặc máy chủ DNS sẽ gửi một máy chủ DNS nhắn Tên Yêu cầu truy vấn có chứa một FQDN tương ứng với một địa chỉ IPv4 trong không gian tên ngược lại, với hướng dẫn để trả lại tất cả RR PTR. | 376 Part IV Application Layer Protocols and Services For AH Transport mode the ICV calculation is performed over the following All the fields in the IP header except those that are allowed to change in transit. These fields are the Type of Service TOS Flags Fragment Offset Time to Live TTL and Header Checksum all of which are set to 0 for the ICV calculation. For source-routed IP traffic the final destination IP address is predictable and the appropriate fields within the Loose Source Route and Strict Source Route options are allowed to change. All the fields in the AH the Authentication Data field is set to 0 . The IP packet payload. For AH Transport mode the AH protects the IP header except the fields that are allowed to change and the payload of the original IP datagram. The following is Frame 10 of Capture 18-01 in the Captures folder on the companion CD-ROM which shows an AH-protected Domain Name System DNS Name Query Request message as displayed by Network Monitor Frame Ethernet Etype Internet IP IPv4 - Ipv4 Next Protocol AH Packet ID 1807 Total IP Length 86 Versions IPv4 Internet Protocol Header Length 20 DifferentiatedServicesField DSCP 0 ECN 0 TotalLength 86 0x56 Identification 1807 0x70F FragmentFlags 0 0x0 TimeToLive 128 0x80 NextProtocol AH 51 0x33 Checksum 11405 0x2C8D SourceAddress DestinationAddress Chapter 18 Internet Protocol Security IPsec 377 - Ah Next Protocol UDP SPI 0x48b7d428 Seq 0x1 NextHeader UDP 17 0x11 PayloadLength 24 bytes Reserved 0 0x0 SecurityParametersIndex 1220006952 0x48b7d428 SequenceNumber 1 0x1 AuthenticationData 12 UINT8 s Udp SrcPort 50286 DstPort DNS 53 Length 42 Dns QueryId 0xDE8D QUERY Standard query Query for of type Host A ddr on class Internet AH Tunnel Mode Figure 18-3 shows AH Tunnel mode for an IP datagram. Figure 18-3 AH Tunnel mode In AH Tunnel mode the entire original IP datagram is encapsulated with a new outer IP header and an AH. In the IP header the Protocol field .