1 Protocol Classification
1.1 Network layer protocol
IP 、 ICMP、IGMP、IS-IS、IPsec、 ARP、 RARP、RIP、VRRP等
1.2 Transport layer protocol
TCP、 UDP、TLS、SSL、OSPF 等
1.3 Application layer protocol
DHCP 、DNS 、FTP、 HTTP、POP3、 SNMP 、SSH 、TELNET 、 BGP 、GLBP、HSRP等
2 Protocol Details
2.1 IP protocol
IP refers to Internet Interconnection Protocol, the abbreviation of Internet Protocol, which is the network layer protocol in the TCP/IP system.
2.2 IPsec protocol
The Internet Security Protocol (Internet Protocol Security, IPSec) is a protocol package that protects the network transmission protocol cluster (a collection of some interrelated protocols) of the IP protocol by encrypting and authenticating the packets of the IP protocol.
2.3 ARP protocol
Address Resolution Protocol, or ARP (Address Resolution Protocol), is a TCP/IP protocol that obtains a physical address based on an IP address.
2.4 RARP protocol
Reverse Address Resolution Protocol (RARP: Reverse Address Resolution Protocol) allows physical machines in the LAN to request their IP addresses from the ARP table or cache of the gateway server.
2.5 RIP protocol
Routing Information Protocol (RIP) is a distance vector protocol, which means it uses the number of hops to determine the best route to a destination.
2.6 VRRP protocol
VRRP virtual router redundancy protocol, VRRP uses virtual routers to control which physical routers are assigned to the access network, a VRRP group consists of a primary router and one or more backup routers that share a virtual IP address, if the primary router fails, VRRP automatically assigns one of the backup routers without affecting network traffic. When the failed router is operational again, it becomes the primary router again. VRRP provides this redundancy without user intervention or additional configuration of any devices on the network. The VRRP master router sends VRRP notification messages to the backup router. When the VRRP master router fails to send the notification message, the backup router with the highest priority takes over as the master router.
2.7 TCP protocol
Transmission Control Protocol (TCP, Transmission Control Protocol) is a connection-oriented, reliable, byte-stream-based transport layer communication protocol, and TCP is designed to adapt to the layered protocol hierarchy supporting multiple network applications. TCP is used to provide reliable communication services between pairs of processes in host computers connected to different but interconnected computer communication networks.
2.8 UDP protocol
The protocol is called User Datagram Protocol (UDP, User Datagram Protocol). UDP provides a way for applications to send encapsulated IP packets without establishing a connection. It is a connectionless transport layer protocol in the OSI (Open System Interconnection) reference model, providing transaction-oriented simple and unreliable information transmission services.
2.9 TLS protocol
Transport Layer Security (TLS) is used to provide confidentiality and data integrity between two communicating applications. The protocol consists of two layers: TLS Record Protocol (TLS Record) and TLS Handshake Protocol (TLS Handshake).
2.10 SSL protocol
SSL (Secure Sockets Layer), and its successor, Transport Layer Security (TLS), is a security protocol that provides security and data integrity for network communications. TLS and SSL encrypt network connections between the transport layer and the application layer.
2.11 DHCP protocol
DHCP Dynamic Host Configuration Protocol is a network management protocol. DHCP runs at the application layer to dynamically assign IP addresses to clients. This is achieved by sharing DHCP transactions or DHCP sessions: Step 1: discover: client sends A dhcp discover message notifies the server; step 2: offer: the server responds with an available IP address and other parameters; step 3: request: the client requests an IP address from the server; step 4: acknowledge: the server responds with an available IP address and other parameters.
2.12 GLBP agreement
GLBP gateway load balancing protocol provides redundancy and load balancing. GLBP works on top of UDP (port 3222), that is, at the application layer, GLBP is a virtual gateway protocol similar to HSRP and VRRP. Unlike HSRP or VRRP, it does not would increase any administrative burden.
2.13 HSRP protocol
HSRP hot backup router protocol, CISCO proprietary protocol, first hop redundancy protocol, can use one or more routers for backup.
2.14 IGMP protocol
The Internet Group Management Protocol (IGMP) is a protocol corresponding to the network layer in the seven-layer framework model of the Open Systems Interconnection (OSI).
2.15 ICMP protocol
The ICMP Internet Control Message Protocol works on the network layer of the OSI model and the Internet layer of the TCP/IP model. ICMP messages are not directly transmitted to the data link layer.
2.16 BGP protocol
BGP Border Gateway Protocol, an Exterior Gateway Protocol EGP, belongs to the Path Vector Protocol, based on TCP/IP, runs on the OSI Transport Layer (Layer 4) to control the Network Layer (Layer 3),
2.17 IS-IS protocol
IS-IS intermediate system to intermediate system, IS-IS was originally designed as a dynamic routing protocol of ISO CLNP, defined in the ISO 10589 standard, belonging to IGP, a link state routing protocol, similar to the link state routing protocol of OSPF.
2.18 EIGRP protocol
EIGRP enhanced interior gateway routing protocol, Cisco's proprietary hybrid routing protocol, belongs to IGP (Interior Gateway Protocol), uses DUAL diffusion update algorithm, has distance vector and link state routing protocol attributes, supports classless routing, VLSM, routing summary , load balancing and many other useful features.
2.19 OSPF protocol
OSPF Open Shortest Path First. OSPF is one of the IP routing protocol series, and is the Internet's interior gateway protocol (IGP), used to distribute IP routing information in a single autonomous system (AS) in an IP network. OSPF is a network layer protocol, applicable to protocol number 89 and AD value 110. OSPF uses the multicast address 224.0.0.5 for normal communication and 224.0.0.6 for updates to Designated Router (DR)/Backup Designated Router (BDR).
2.20 HRP protocol
HRP is Huawei's redundancy backup protocol. The Eudemon firewall uses this protocol for backup networking to achieve the purpose of link state backup, so as to ensure normal service when a device fails. VGMP (vrrp group management protocol) is the group management protocol of VRRP, and the VGMP protocol is also Huawei's proprietary protocol. VGMP manages by adding VRRP to a group, negotiates with the peer end through VGMP packets, determines the VGMP status of itself and the peer end, and changes the status of VRRP under the VGMP group to and The status of VGMP is consistent. The VRRP of the firewall is the same as the standard VRRP protocol. The configuration of VRRP is briefly described below. For details, please refer to the relevant RFC. On the firewall, if VRRP is added to VGMP, the state of VRRP is determined by VGMP, and no longer needs to be negotiated by itself.
2.21 EIGRP protocol
EIGRP is an advanced Cisco-based distance vector routing protocol that works on the principle of an interior gateway protocol, uses incremental and triggered updates, improves operational capabilities and fast convergence speed, can determine the shortest path distance vector, and uses bandwidth, load And delay and other indicators to calculate the shortest optimal network route. EIGRP is a complex protocol, but it is easy to configure and operate in small and large networks.
2.22 NAT protocol
NAT (Network Address Translation) is the process of converting one or more local private IP addresses into a global public IP address, through which multiple local devices and hosts can be allowed to access the Internet. NAT works on a router or firewall to protect a private network, all devices in a local network have different private IP addresses, while the public IP address they use can be the same, generally speaking, if you google "my What is the IP" and you will find the exact public IP address used by localhost.
2.23 BGP protocol
Border Gateway Protocol (BGP) is a protocol that helps routers find the shortest path to a destination and provides an alternate route if the shortest path is blocked. BGP can instruct routers how to reach the final IP address. Technically, BGP is a protocol for exchanging routing information between adjacent autonomous systems (AS).