|
IP In IP
IP in IP is an IP tunneling protocol that encapsulates one IP packet in another IP packet. To encapsulate an IP packet in another IP packet, an outer header is added with Source IP, the entry point of the tunnel, and Destination IP, the exit point of the tunnel. While doing this, the inner packet is unmodified (except the TTL field, which is decremented). The Don't Fragment and the Type Of Service fields should be copied to the outer packet. If the packet size, including the outer header, is greater than the Path MTU, the encapsulator fragments the packet. The decapsulator will reassemble the packet. packet encapsulated in IP packet Outer IP header has the following fields: Version: 4 bitsThis field is the Protocol version number. It is always 4 as IP in IP is supported for IPv4 Header Length: 4 bits This field is the length of outer IP header Type of Service (TOS): 8 bits This field is copied from the inner IP header Total Length: 16 bits This field is the length of the en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IP Tunnel
An IP tunnel is an Internet Protocol (IP) network communications channel between two networks. It is used to transport another network protocol by encapsulation of its packets. IP tunnels are often used for connecting two disjoint IP networks that don't have a native routing path to each other, via an underlying routable protocol across an intermediate transport network. In conjunction with the IPsec protocol they may be used to create a virtual private network between two or more private networks across a public network such as the Internet. Another prominent use is to connect islands of IPv6 installations across the IPv4 Internet. In IP tunnelling, every IP packet, including addressing information of its source and destination IP networks, is encapsulated within another packet format native to the transit network. At the borders between the source network and the transit network, as well as the transit network and the destination network, gateways are used that establish t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Transmission Unit
In computer networking, the maximum transmission unit (MTU) is the size of the largest protocol data unit (PDU) that can be communicated in a single network layer transaction. The MTU relates to, but is not identical to the maximum frame size that can be transported on the data link layer, e.g. Ethernet frame. Larger MTU is associated with reduced overhead. Smaller MTU values can reduce network delay. In many cases, MTU is dependent on underlying network capabilities and must be adjusted manually or automatically so as to not exceed these capabilities. MTU parameters may appear in association with a communications interface or standard. Some systems may decide MTU at connect time, e.g. using Path MTU Discovery. Applicability MTUs apply to communications protocols and network layers. The MTU is specified in terms of bytes or octets of the largest PDU that the layer can pass onwards. MTU parameters usually appear in association with a communications interface ( NIC, serial port, et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time To Live
Time to live (TTL) or hop limit is a mechanism which limits the lifespan or lifetime of data in a computer or network. TTL may be implemented as a counter or timestamp attached to or embedded in the data. Once the prescribed event count or timespan has elapsed, data is discarded or revalidated. In computer networking, TTL prevents a data packet from circulating indefinitely. In computing applications, TTL is commonly used to improve the performance and manage the caching of data. Description The original DARPA Internet Protocol's RFC document describes TTL as: IP packets Under the Internet Protocol, TTL is an 8-bit field. In the IPv4 header, TTL is the 9th octet of 20. In the IPv6 header, it is the 8th octet of 40. The maximum TTL value is 255, the maximum value of a single octet. A recommended initial value is 64. The time-to-live value can be thought of as an upper bound on the time that an IP datagram can exist in an Internet system. The TTL field is set by the sender ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of IP Protocol Numbers
This is a list of the IP protocol numbers found in the field ''Protocol'' of the IPv4 header and the ''Next Header'' field of the IPv6 header. It is an identifier for the encapsulated protocol and determines the layout of the data that immediately follows the header. Both fields are eight bits wide. Protocol numbers are maintained and published by the Internet Assigned Numbers Authority (IANA). {, class="wikitable" , - ! Hex ! Protocol Number !! Keyword !! Protocol !! References/RFC , - , 0x00 , 0 , HOPOPT , IPv6 Hop-by-Hop Option , , - , 0x01 , 1 , ICMP , Internet Control Message Protocol , , - , 0x02 , 2 , IGMP , Internet Group Management Protocol , , - , 0x03 , 3 , GGP , Gateway-to-Gateway Protocol , , - , 0x04 , 4 , IP-in-IP , IP in IP (encapsulation) , , - , 0x05 , 5 , ST , Internet Stream Protocol , , , - , 0x06 , 6 , TCP , Transmission Control Protocol , , - , 0x07 , 7 , CBT , Core-based trees , , - , 0x08 , 8 , EGP , Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Control Message Protocol
The Internet Control Message Protocol (ICMP) is a supporting protocol in the Internet protocol suite. It is used by network devices, including routers, to send error messages and operational information indicating success or failure when communicating with another IP address, for example, an error is indicated when a requested service is not available or that a host or router could not be reached. ICMP differs from transport protocols such as TCP and UDP in that it is not typically used to exchange data between systems, nor is it regularly employed by end-user network applications (with the exception of some diagnostic tools like ping and traceroute). ICMP for IPv4 is defined in RFC 792. A separate ICMPv6, defined by RFC 4443, is used with IPv6. Technical details ICMP is part of the Internet protocol suite as defined in RFC 792. ICMP messages are typically used for diagnostic or control purposes or generated in response to errors in IP operations (as specified in RFC 1122 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generic Routing Encapsulation
Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco Systems that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links or point-to-multipoint links over an Internet Protocol network. Example uses * In conjunction with PPTP to create VPNs. * In conjunction with IPsec VPNs to allow passing of routing information between connected networks. * In mobility protocols. * In A8/A10 interfaces to encapsulate IP data to/from Packet Control Function (PCF). * Linux and BSD can establish ad-hoc IP over GRE tunnels which are interoperable with Cisco equipment. * Distributed denial of service (DDoS) protected appliance to an unprotected endpoint. Example protocol stack Based on the principles of protocol layering in OSI, protocol encapsulation, not specifically GRE, breaks the layering order. It may be viewed as a separator between two different protocol stacks, one acting as a carrier for another. Delivery protocols GRE pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
6in4
6in4 is an IPv6 transition mechanism for migrating from Internet Protocol version 4 (IPv4) to IPv6. It is a tunneling protocol that encapsulates IPv6 packets on specially configured IPv4 links according to the specifications of . The IP protocol number for 6in4 is ''41'', per IANA reservation. The 6in4 packet format consists of the IPv6 packet preceded by an IPv4 packet header. Thus, the encapsulation overhead is the size of the IPv4 header of 20 bytes. On Ethernet with a maximum transmission unit (MTU) of 1500 bytes, IPv6 packets of 1480 bytes may therefore be transmitted without fragmentation. 6in4 tunneling is also referred to as ''proto-41 static'' because the endpoints are configured statically. Although 6in4 tunnels are generally manually configured, the utility AICCU can configure tunnel parameters automatically after retrieving information from a Tunnel Information and Control Protocol (TIC) server. The similarly named methods 6to4 or 6over4 describe a different mechanis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4in6
4in6 refers to tunneling of IPv4 in IPv6 Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communication protocol, communications protocol that provides an identification and location system for computers on networks and routes traffic .... It is an Internet interoperation mechanism allowing Internet Protocol version 4 (IPv4) to be used in an IPv6 only network. 4in6 uses tunneling to encapsulate IPv4 traffic over configured IPv6 tunnels as defined in . 4in6 tunnels are usually manually configured but they can be automated using protocols such as TSP to allow easy connection to a tunnel broker. References {{reflist IPv6 transition technologies Tunneling protocols Network protocols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
