hdlc

encapsulate it as the HDLC frame sending. After RT3 is received from the S0/1 interface, remove the layer-2 frame header, view the MPLS label incoming label number 20, find the MPLS Forwarding Table outgoing label number 20, the outbound interface is F1/0, the MPLS label number is 20, the EXP bit is 0, and the stack bottom is 1, at the same time, the TTL-1 (forwarding an MPLS TTL-1 but the TTL in the IP is unchanged, it only involves two layers), and

method needs to be configured at both ends of the vro. For example, if vroa A is packaged with HDLC and vrob B is packaged with PPP, The lineprotocol of the two vrouters is always down. Change the packaging method:Router # conf tRouter (config) # interface serial 0Router (config-if) # encapsulation pppRouter (config-if) # ^ ZRouter #C. If Newbridge's 26XX and 27XX DTU devices do not send CD signals, set the following on the router:Router # configure

features and describe how to use different working modes? Apache has two working modes: prefork (default installation mode of apache) and worker (you can add the parameter -- with-mpm-worker to select the working mode during compilation) prefork features: (pre-derived) 1. this mode eliminates the need to generate new processes when requests arrive, thus reducing system overhead 2. can prevent accidental memory leakage 3. when the server load drops, the number of sub-processes is automatically r

Wan Interface ConfigurationSeven, POS interface configuration and ManagementThe POS (Packet over SONET/SDH) interface can take advantage of SONET (synchronous Optical Network, synchronous fiber network) or SDH (synchronous Digital Hierarchy, Synchronous digital System) provides the high-speed transmission channel directly transmits the IP data service, is widely used in the metropolitan area network and the WAN.In the AR G3 router family, the POS interface is provided by the 1STM1 or 1STM4 inter

Crc-ccitt X16+x12+x5+1 0x1 ' 1021 0x1021 ISO Hdlc,itu X.25,v.34/v.41/v.42,ppp-fcs CRC-32 Note 0x1 ' 04c11db7 0x04c11db7 ZIP,RAR,IEEE 802 Lan/fddi,ieee1394,ppp-fcs Note * x32+x26+x23+x22+x16+x12+x11+x10+x8+x7+x5+x4+x2+x+1The resulting polynomial g (x) in the following table is also common: Name Generating a polynomial Numerical formula Précis-writ

Session LayerSession Layer such as ASAP, SSH, ISO 8327/ccitt x.225, RPC, NetBIOS, ASP, Winsock, BSD sockets4 Transport LayerTransport Layer such as TCP, UDP, TLS, RTP, SCTP, SPX, ATP, IL3 Network layerNetwork layer such as IP, ICMP, IGMP, IPX, BGP, OSPF, RIP, IGRP, EIGRP, ARP, RARP, x.2 Data Link layerData Link layer such as Ethernet, Token Ring, HDLC, Frame Relay, ISDN, ATM, IEEE 802.11, FDDI, PPP1 Physical layerPhysical layer such as line

, understand the memory, because it is basically the model we meet in the actual)The same bottom-up features are:The network access layer, which is not described in detail in the TCP/IP reference model, simply indicates that the host must be connected to the network using some kind of protocol. (Network Interface Layer)The common interface layer protocols are:Ethernet 802.3, Token Ring 802.5,X.,Frame Relay,Hdlc, PPP ATM, and so on. The Internet tier (

common two-layer protocol is: Ethernet, PPP, HDLC, Frame Relay, ATM, etc. The physical layer defines a physical medium-related protocol: the Electronic/Optical protocol (voltage, light intensity, coding, signal Waveform) mechanical protocol (dimensions, metal components of conductors) functional protocol (description of what to do) procedural protocol (describes how to do this: 1 indicates a voltage less than -3v)TCP protocolExplainTransmission Contr

OSI (open System Interconnection), open Systems Interconnect Reference Model. From bottom to top seven-tier model features and their representative protocols: Physical Layer (physical) : Specifies the mechanical, electrical, functional, and process characteristics that activate, maintain, and close communication endpoints. This layer provides a physical medium for the upper level protocol to transmit data. bit, bit. Typical protocol representatives: eia/tia-232, eia/tia-499, v.35, v.24, RJ45

Layer : Conversations between processes are also known as sessions, and the session layer manages conversations between processes on different hosts.Presentation Layer : Provides a formatted representation and transformation Data service for the application-tier process.Application Layer : Provides the means by which applications access the OSI environment.2. The Iso/osi Reference model corresponds to each layer in the TCP/IP protocol model:3. Encapsulation and decryption of data:4. OSI Network

. CN23 Layer (IPSec)WAN access ModeWireless, traditional wired ADSL, coaxial cable (TV signal Conversion Network digital), Ethernet accessVpn:is a connection between multiple private networks on a public networkAdvantages: Low cost, scalable to good, compatibility with broadband technologyConnection modes: Ipsec,gre,mpls Vpn,l2vpn$############################################################################################################## ########################################################

ACL or query the route first? (10 points)ACL is higher than route3 When an ACL is configured on an interface with a packet-out direction, is the ACL checked first or Anza? (10 points)route higher than ACL5 is the ACL written below reasonable? (10 points)Access-list 1 Deny 192.168.1.0Access-list 1 Deny 192.168.1.0 0.0.0.255Did not write permit anyPPP 1 What are the three types of WAN data link layer encapsulation? (10 points)FR Frame Relay, PPP point-to-point,

The upper application encapsulates the data into an IP packet and then encapsulates it into a frame (the router receives a data frame, forwards a data frame, not a packet, he simply takes the number of received frames apart, exposing the three-layer header, The IP address in the header in the packet is only to determine the destination of the forwarding. frame = Frame Header control information + data part + Frame endThe format of the frame is determined by the encapsulation protocol of the i

/CONTENTIONSLOT.O WIMAX/SCHEDULING/CONTENTIONREQUEST.O WIMAX/SCHEDULING/CONTENTIONTIMER.O WIMAX/SCHEDULING/DLBURST.O wimax/ SCHEDULING/ULBURST.O WIMAX/SCHEDULING/FRAMEMAP.O WIMAX/SCHEDULING/PHYPDU.O WIMAX/SCHEDULING/PROFILE.O wimax/ SCHEDULING/SUBFRAME.O WIMAX/SCHEDULING/SCANNINGSTATION.O WIMAX/SCHEDULING/WIMAXCTRLAGENT.O \(3) on the No. 570 line of "@[email protected]" above, another line, addTCL/LIB/NS-WIMAX.TCL \6. Edit the Packet.h file in the Ns-2.35/common directory:(1) on the No. 202 line

,mpeg,quicktimeIii. Session Layer: NFS, SQL, RPC, X-windows, ASP (apptalk Session protocol), SCPIv. Transport Layer: TCP, UDP, SPXFive, Network layer: IP, IPX, ICMP, RIP, OSPF (Open Shortest Path first opening shortest path priority)Vi. Data Link layer: SDLC, HDLC, PPP, STP (Spanning Tree Protocol), Frame RelayVii. Physical layer: Eia/tia RS-232, Eia/tia RS-449, v.35, RJ-45Common network interconnection devices at each level:Physical layer: Repeater,

WAN ( Wide Area Network ) WanThe data link layer, the physical layer, running in the OSI model.The protocols of the data link layer are mainly:HDLC (High-level Data Link control)PPP (Point-to-point Protocol-to-dot protocol)Frame-relay (Frame Relay)ATM (asynchronous Transfer mode Asynchronous transfer model)configuration of the serial port ( Serial Interface )R1 (config) #interface serial 0/1R1 (config-if) #ip Add 1.1.1.1 255.255.255.0R1 (config-if) #clock rate 128000//dce end needs configuration

checking, re-sending and so on. It is independent of the network layer and the physical layer, and works without worrying about whether the computer is running software or other operations. The Data Link layer protocol includes: SDLC, HDLC, PPP, STP, Frame Relay, and so on.the third layer of the OSI model: Many users of the network layer often confuse the 2-layer and 3-tier issues, so if you're talking about a problem with an IP address, routing prot

How should we understand network communication protocols? Can we fully master the increasingly complex network structures? We need to rely on network communication protocols for learning and understanding. 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 accepted by both parties. To implement the OSI Layer-7 reference model function, each layer has many c

transitionsDCD = upDSR = upDTR = upRTS = upCTS = up As you can see, the router uses the PPP protocol for encapsulation and the interface is in normal state. Ping R2 on R1, as shown below: R1 # ping 12.1.1.2 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 12.1.1.2, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 20/25/40 MS In this case, after the PPP encapsulation, the direct connection is normal. 3. view the PPP Encapsulation Format as

=" 0 "vspace=" 0 "alt=" wkiol1sote_sm4vpaacwspeapqg860.jpg "style=" width:718px ; height:62px; "/>2, enter the port mode: (The following several steps, respectively) Router (config) #int s1/1A, change the data packaging method (the serial port by default, the package is: HDLC Ethernet: ARPA) Router (config-if) #encapsulation Frame-relayB, sealing and binding relayC, Binding Relay interface type Router (config-if) #frame-relay intf-type DCED. Define th