hdlc

1. Which of the following is NOT a required condition for deadlock () A. mutex ConditionsB. Inaccessible NetworksC. Resource deprivationD. Loop waitE. Waiting for possession 2. Write the name of the corresponding OSI model layer on the right according to the concept given on the left. Devices and concepts Name EIA \ Tia RS-232, network card Physical Layer TCP and UDP Transport Layer IP, ARP, and OSPF Network Layer HTTP, DNS, ftp Applica

. Generally, the frame has a frame header and a frame tail, and the source object L2 address in the header, while the frame tail usually contains verification information, the content between the beginning and end is the user data. The data link layer provides many functions, so it is divided into two sub-layers: the MAC (Media Access Control) layer and the LLC (Logical Link Control) layer. The common L2 standard for LAN and man is IEEE 802 protocol. In the wide area network,

overhead. Comparison of Three Types of forwarding Network layered protocol model Name the PDU based on the protocol of the TCP/IP protocol cluster: Application Layer data generally refers to the PDU used by the application layer. Transport Layer Data Segment transport layer PDU Network layer packet network layer PDU Link layer frame network access layer PDU The PDU used when the physical layer bit (BIT) actually transmits data through the media OSI 7-component protocol model App

Cisco HDLC encapsulation protocol. 2. Example The S0 ports of router Router1 and Router2 both encapsulate the PPP protocol and adopt CHAP for authentication. In Router1, a user should be created and the peer vro host name should be used as the user name, that is, the user name should be router2. At the same time, a user should be created in Router2, with the peer router host name as the user name, that is, the user name should be router1. The passwor

of the interface from which the unnumbered interface borrows the IP address. It cannot be another unnumbered interface. If you want to disable the I P processing function in the serial interface, you can use the NO form of this command. No number interface restrictions:* Serial interfaces using HDLC, PPP, LAPB, and SLIP protocols and tunnel interfaces can be Unnumbered. It cannot be in X. 25. Use the unnumbered interface to configure commands on the

Frame-Rekay ): Frame relay is a connection-oriented service. It is an industry standard pure L2 data link layer protocol. It uses HDLC encapsulation between connected devices and can process multiple virtual circuits (VC; frame Relay is more effective than X.25. Currently, it is generally considered that frame relay should be used to replace X.25; Virtual link VC (Virtual Circuits): Permanent Virtual link PVC (Permanent VC) and switched Virtual li

be invalid for a period of time. Figure 1 CHAP CHAP has high requirements on the end system because it requires multiple identity questions and responses. This requires a lot of CPU resources, so it is only used in scenarios with high security requirements. 3. CHAP Configuration Basic PPP Configuration For synchronous serial interfaces, the default Encapsulation Format is HDLCCisco private implementation ). You can use the encapsulation ppp command to change the encapsulation Format to PPP.2.

standards 1. E1: 64k-2Mbps. 2. X25: The maximum speed is 64 kbps. 3. Frame Relay: The E1 circuit is used, and the speed can be 64 K to 2 Mbps. 4. V24: the router end is a DB50 connector, and the external network end is a 25-pin connector. In asynchronous mode, the link layer protocol PPP is encapsulated and Network Layer Protocol IP address and IPX are supported. The maximum transmission rate is 115200bps; In synchronous mode, link layer protocols such as X.25, frame relay, PPP,

router has 1 10 m lan (LAN) Port, 2 WAN ports and 1 Console port. Therefore, the features of the backup line are met in this scenario. Wan interfaces support Frame Relay, X.25, PPP, HDLC, and other Wan protocols, provide transmission rates up to T1/E1, and provide network address translation (NAT) functions. Supports PAD (X.3, X.28, and X.29) protocols and provides password protection. Based on this network application scenario, you can select the 3C

define the communication between the terminal system and the intermediate system ｡ RD (Routing Domain, Routing Domain). In a Routing Domain, a group of IS exchange Routing information through the same Routing protocol ｡ Area. The unit of the route field ｡ LSDB (Link State DataBase, Link State DataBase). All network connection States constitute a Link State DataBase, and each IS has at least one LSDB. IS uses the SPF algorithm, use LSDB to generate your own route ｡ LSPDU (Link State Protocol Dat

current internet, two-way routing is asymmetric: the path from host a to host B is not necessarily the opposite of the path from host B to host a; the other, the data transmission features in both directions and the resources reserved for the corresponding application may not be the same. Resource Reservation Protocol (RSVP) provides two types of reservation: Dedicated reservation (distinct reservation): the required reserved resources are only used by one sender. That is, different senders in

support for sync tty ports ; PPP Deflate compression ; Ppp bsd-Compress compression ; Microsoft PPP compression/encryption (MPPC/MPPE) ; PPP over Ethernet (EXPERIMENTAL) Character devices -->; Non-standard serial port support[M] hdlc line discipline supportCryptographic options --->;[M] SHA1 digest algorithm[M] ARC4 cipher algorithmRec

This article analyzes the reasons why the ADSL2 standard has become a new favorite of the network. There are many problems with the ADSL2 standard on the network. For various ADSL2 standards, the following is a question and answer topic, hoping to cover all questions about the use of ADSL2 standards by netizens. Enhanced interoperability In the ADSL2 standard, more parameters will be transmitted during the training phase. In addition, many parameters are determined by the receiver end rather tha

The foundation of the network is the establishment and application of many computer network protocols. So how can we understand this concept? The following describes the overview of computer network communication protocols. Network Communication Protocol (Network Communication Protocol )) it is a set of definitions of the Information Format for communication between computers and the transfer content that can be received or accepted by both parties. to implement the OSI Layer-7 reference model f

large. 3. OSPF network type Based on the physical network connected by the router, OSPF divides the network into four types: Broadcast multiAccess and non-Broadcast MultiAccess) point-to-Point and Point-to-MultiPoint ). Broadcast Multi-Channel Access networks such as Ethernet, Token Ring, and FDDI. NBMA networks such as Frame Relay, X.25, and SMDS. Point-to-Point networks such as PPP and HDLC. 4. assign a router (DR) and a backup router (BDR) Multipl

connections for applications on two hosts, enabling peer entities on the source and target hosts to perform sessions. The transport layer protocols in the TCP/IP protocol family mainly include TCP and UDP. TCP is connection-oriented, which ensures reliable transmission between the two ends of the communication and supports recovery in disorder, error retransmission, and traffic control. While UDP is connected, it provides non-reliability data transmission, and the reliability of data transmissi

before sending data on the media, common L2 protocols include Ethernet, PPP, HDLC, frame transfer, ATM, etc. The physical layer defines the Protocols related to the physical media: electronic/Optical protocols (voltage, light intensity, coding, Signal Waveforms) Mechanical protocols (dimensions, metallic composition of wires) Functional protocols (description of what to do) procedural protocols (describes how to do such: 1 indicates the voltage is le

. Otherwise, the two routers cannot become neighbors.4. Stub area label: two routers can negotiate the label of the Stub area in the Hello message to become neighbors. This content will be mentioned later in the blog post.Ii. Network Interface Type of OSPF:1. Point-to-Point)A point-to-point network is a pair of independent routers. Indicates that the network includes PPP and HDLC.2. Broadcast)A broadcast Multiple Access Network is a multi-access netwo

exceeding the specified bandwidth: ip rtp priority {starting-rtp-port-number-range} {bandwidth} max-reserved-bandwidth PERCENTshow queue [interface] debug priorityCRTP (compression Real-Time Protocol ): there are three compression methods for compressing ip/udp/rtp headers: link compression, payload compression, and header compression layer 2 header-TCP/IP Header-payload 1. link compression: the entire group is compressed. Compression, including header and payload. Independent from the protocol

, minimize packet loss and resend. PPTP gives the customer the initiative to establish a tunnel, but the customer needs to configure PPTP on its PC. This will increase the user's workload and cause network security risks. In addition, PPTP only works on IP addresses and does not have the function of verifying the tunnel endpoint. It depends on user verification. L2F/L2TP protocol: The L2F (Layer 2 Forwarding) protocol is proposed by Cisco to establish a multi-protocol secure VPN communication mo