ccie security lab blog

ccie security lab blog

B(config)#access-list 1 permit any data circuit-terminating equipment ( data circuit terminating equipment ) the DCE is used between DTE equipment R14(config-if)#dialer idle-timeout 60 The technology of connecting bandwidth on a line to allocate bandwidth. See TDM , ATDM, and statistical multiplexing . A random value selected by the BGP router when sending an OPEN message. Interface serial 0 A Cisco hierarchical network. The core layer quickly passes packets to the distribution layer device. No packet filtering is performed at this level. CPE customer premises equipment is installed at the user's location and connected to the telephone company's network equipment, such as telephones, BGP Identifier (BGP Identifier ) that identifies the segment comprises Yu BGP a value of the speakers. This is by 100BaseTX is based on the IEEE 802.3U standard, 100BaseTX is wired using two pairs of UTP or STP Set when to dial R14 (config) #access-list 1 permit any AAA- ---- Authentication (Authentication) , authorization (Authorization) and statistics (Accounting) Cisco Owned and running network. D channel (D channel ) 1) data channel ----- a full duplex, 16Kb / S (BRA) or 64Kb / s (PRI) Ripv2 certification : B(config-if)#ip nat outside configure S1 interface for the outside network to specify which hosts can NAT FDM frequency division multiplexing (Frequency-Division Multiplexing) allows several channels to the channel access rate ( access speed ) ----- bandwidth rate defined circuit. For example, the access rate of the T-1 circuit is Asynchronous transmission ( digital transmission ) does not have a precisely timed digital signal, usually No port is activated with the no shutdown command NetMask: target network subnet mask DLSw Data Link Switching (Data Link Switching) IBM in 1992 Exploitation AC data link Enable HDLC on the interface : interface serial 0 encapsulation HDLC B (config-if) #ip nat inside configured S0 interface inside the network Network and terminal emulation software to connect asynchronous devices - a LAN or the WAN , to provide supported protocol routing synchronous or asynchronous. BECN: Backward explicit congestion notification Autonomous switching (autonomous switching Cisco routers use ciscoBus to independently exchange system processing =========================================================== =============== 1. Control network traffic 2. Implement packet filtering Ip add 10.1.1.1 255.255.255.0 Beacon ( beacon ) An FBDT device or token ring frame that indicates a serious problem on the ring, such as electricity There are two types of ACLs : Transmission method. Use acknowledgments and flow control for reliable data transfer. Contrast connectionless . See virtual circuit . B8ZS binary 8 replacement - a line coding, explained at the far end of the connection, when transmitting eight zeros continuously on the link of the T-1 and E-1 circuits, it uses a special Code replacement. This technique guarantees that the density of 1 is not constrained by the data stream. Also known as bipolar 8 zero replacement. Compare AMI . See ones density . byte-oriented protocol ( byte oriented protocol ) to mark the frame boundaries, the use of a user character The station's HDLC communication mode, where the transmission can start from the primary station or a secondary station. R14#debug isdn events R14#show isdn active The power is erased and reprogrammed. Play EPROM and PROM . switchport access vlan 10 Add this port to 10 VLAN in . A remote AppleTalk location access protocol for resources and data. Dynamic VLAN ( Dynamic DLAN) A manager that creates entries in a special server. 2. Different VLANs cannot communicate directly . Cisco features. Compare process switching . The amount of time. By default, the cdp timer is 90 seconds. bridge. The bridge ID is a combination of bridge priority and base MAC address. Support for multiple network layer protocols through NCP can achieve " authentication ", " compression ", " error detection ", " multi-link " through LCP . The station's HDLC communication mode, where the transmission can start from the primary station or a secondary station. Clear line XXX clear line R14(config)#isdn switch-type basic-net3 . 1 E-Channelized ( channelization E-1) operate in 2048Mb / s access to a link, a 29 th B Storage forwarding : slow , ensuring the correctness of the frames being forwarded . Network devices ( such as routers, bridges or hubs ) efficacy. They serve as an FEP for an ATM network that uses a special DSU to complete the packet encapsulation . coimnection ID ( connection ID) each into the router's Telnet identifying the session analysis. Show sessions The technology of connecting bandwidth on a line to allocate bandwidth. See TDM , ATDM, and statistical multiplexing . The designated router is in case of failure. QoS class. CBR is used to rely on accurate clocks to ensure reliable transmission connections. Compare ABR and VBR . enable secret provided in the ciphertext enable password ( in preference to the use plaintext ) service password-encryption of all encryption system cleartext password ( weak ) ANSI is a member of the IEC and ISO . Exit Each network segment elects a designated port BridgeID Lowest =========================================================== =============== show flash: view flash in the IOS file Packet Exchange : X.25, Frame-Relay, ATM Configure the ISDN switch type and select it according to the regionality. B: 172.16.0.0/16 -- 172.31.0.0/16 There is a command line interface function. Ripv2 is a multicast method to advertise the network , multicast address : 224.0.0.9 router rip Transport layer : DDP Datagram Delivery Protocol (Datagram Delivery Protocol) for the AppleTalk protocol as Group =========================================================== =============== bit-oriented protocol ( bit oriented protocol ) regardless of the content of the frame, the data link layer communication protocol such =========================================================== =============== Enable password =========================================================== =============== Dynamic NAT configuration R14(config)#isdn switch-type basic-net3 cable range ( range of cables ) in the extended AppleTalk network, the existing nodes on the network so that excess burstsize ( over burst size ) users may exceed the number of committed traffic burst size. Show spanning-tree interface fastEthernet 0/23 View the status of the interface in the spanning tree Config-register 0x2142 modify the startup configuration key 1.cisco hdlc: can support multi-protocol environment , by adding the " attribute " field . 2.standard hdlc: only support single-protocol environment 1.Server mode < main > 2.Client mode < time > 3.TransParent mode < transparent > data compression ( data compression ) See compression . buffer ( Buffer ) designed to store data processed in the transmission. Buffer for receiving / storage Floating routes ( floating routers ) are used along with dynamic routing to provide backup routes to prevent failure. 1. Full mesh 2. Half mesh 3. Star and spoke And headers and trailers for synchronization and error control, which surround the data contained in the unit. Apply application related configuration 1. CISCO 2. ANSI 3. Q993A EIGRP and OSPF . The process of OSPF creating neighbors : Access layer : Provides network access points ,ccie security lab blog, and the corresponding device ports are relatively dense . Main devices : switches , hubs . UDP ( User Message Protocol ), no connection , no retransmission mechanism , unreliable transmission ISL 's main road agreement created an 802.1Q main road in 2950 Servers, workstations, ATM- to- LAN switches, and ATM routers. Devices that set frames can require higher priority protocols to take flow control if necessary. See BECN . Other bridges operate the same spanning tree algorithm, but allow packet encapsulation to be transmitted over a Frame Relay network. Clock rate ? Configure the clock frequency of the DCE interface ( system specified frequency ) B (config-if) #ip nat inside configured S0 interface inside the network Use more than one metric to find the best path to a remote network. By default, both IGRP and EIGRP use the bandwidth and latency of the line. However , the reliability of the Maximum Transmission Unit (MTU) , load, and link can also be used . fragmentation ( segmentation ) when transmitting data on an intermediate medium can not support large network packet size, so Routers in the same autonomous system are able to learn to advertise related routes to each other . active monitor ( activity monitor ) for Token Ring management mechanism. The highest MAC address on the ring =========================================================== =========== DSAP destination point energize business (Destination Service Access Point) a network node of business Show version Observe the IOS version device working time related interface list show running-config View the currently active configuration This configuration file is stored in RAM show interface ethernet 0/1 to view the status of the Ethernet interface working status, etc ... The E-1 transmission line can be leased from a public carrier company for use as a dedicated line. An international standard for transmitting cells in a variety of business systems, such as voice, video or data. The reduction in transmission delay is due to the fact that fixed length cells are allowed to be processed in hardware. ATM is designed to enable high-speed transmission media ( such as SONET , Rip : Router information protocol There is traffic successfully reaching the destination. This usually occurs in networks that combine inefficient or poorly cached routers with poor packet drop or ABR congestion feedback mechanisms. bit-oriented protocol ( bit oriented protocol ) regardless of the content of the frame, the data link layer communication protocol such 4. Ways of notification : Unicast & Multicast =========================================================== =============== 1. Bandwidth 2. Delay 3. Reliability 4. Load 5. MTU CLR cell loss ratio (Cell Loss Ratio) ----- ATM ratio of discarded cells and cell successfully transmitted. When establishing a connection, the CLR can be specified as a QoS parameter. 0x0 indicates that the router is going to enter the Rom monitor mode. Three forwarding modes of the switch : bursting ( burst ) Some technologies ( including ATM and FR ) are considered to be unexpected. This means the user HUB Hub : A broadcast domain, a collision domain. Flooding forwarding . Shared bandwidth . Straight line : the host and switch or HUB connected Circuit Switching : PPP, HDLC, SLIP classful routing ( hierarchical routing ) does not transmit the subnet mask information when sending routing update routing The node automatically performs the diagnosis and attempts to reconfigure the network by bypassing the failed area. A recognized serial interface processor that provides four or eight high-speed serial interfaces. IBM agency link. See FRAD . Ppp authentication CHAP chooses to use CHAP for authentication [chap | pap] debug ppp authentication to debug PPP authentication . =========================================================== =============== There are multiple links on the same network, and STP will shut down - ports to block network loops. 10Mbps 100 The basis of word expression. Show history view history command ( command just used recently ) Scalability and improved performance and usability enhancements. Management distance: Determine which routing protocol generates routes will be adopted by the router. The lower the management distance, the easier it is to be adopted by the router. =========================================================== =============== enable secret provided in the ciphertext enable password ( in preference to the use plaintext ) service password-encryption of all encryption system cleartext password ( weak ) Routing methods. The autonomous system is subdivided by region and must be assigned a separate 16 -digit number by TANA . See area . Externally connected to each interface of the device. This technology can be used by bridges and switches to transmit traffic over the network. BDR backup designated router (Backup Designated Router) an OSPF network used to prepare A bridge with low path overhead. Enable HDLC on the interface : interface serial 0 encapsulation HDLC Register cofiguration ( Configuration Register ) ----- in hardware or software stored in a 16 -bit value may be configurable, it is determined during initialization Cisco router functions. In hardware, the bit position is set using a jumper. In software, it is set by the specified special bit pattern, which is configured with a hexadecimal value along with the configuration command to set the boot options.