3Com 10014303 инструкция обслуживания

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Хорошее руководство по эксплуатации

Законодательство обязывает продавца передать покупателю, вместе с товаром, руководство по эксплуатации 3Com 10014303. Отсутствие инструкции либо неправильная информация, переданная потребителю, составляют основание для рекламации в связи с несоответствием устройства с договором. В законодательстве допускается предоставлении руководства в другой, чем бумажная форме, что, в последнее время, часто используется, предоставляя графическую или электронную форму инструкции 3Com 10014303 или обучающее видео для пользователей. Условием остается четкая и понятная форма.

Что такое руководство?

Слово происходит от латинского "instructio", тоесть привести в порядок. Следовательно в инструкции 3Com 10014303 можно найти описание этапов поведения. Цель инструкции заключается в облегчении запуска, использования оборудования либо выполнения определенной деятельности. Инструкция является набором информации о предмете/услуге, подсказкой.

К сожалению немного пользователей находит время для чтения инструкций 3Com 10014303, и хорошая инструкция позволяет не только узнать ряд дополнительных функций приобретенного устройства, но и позволяет избежать возникновения большинства поломок.

Из чего должно состоять идеальное руководство по эксплуатации?

Прежде всего в инструкции 3Com 10014303 должна находится:
- информация относительно технических данных устройства 3Com 10014303
- название производителя и год производства оборудования 3Com 10014303
- правила обслуживания, настройки и ухода за оборудованием 3Com 10014303
- знаки безопасности и сертификаты, подтверждающие соответствие стандартам

Почему мы не читаем инструкций?

Как правило из-за нехватки времени и уверенности в отдельных функциональностях приобретенных устройств. К сожалению само подсоединение и запуск 3Com 10014303 это слишком мало. Инструкция заключает ряд отдельных указаний, касающихся функциональности, принципов безопасности, способов ухода (даже то, какие средства стоит использовать), возможных поломок 3Com 10014303 и способов решения проблем, возникающих во время использования. И наконец то, в инструкции можно найти адресные данные сайта 3Com, в случае отсутствия эффективности предлагаемых решений. Сейчас очень большой популярностью пользуются инструкции в форме интересных анимаций или видео материалов, которое лучше, чем брошюра воспринимаются пользователем. Такой вид инструкции позволяет пользователю просмотреть весь фильм, не пропуская спецификацию и сложные технические описания 3Com 10014303, как это часто бывает в случае бумажной версии.

Почему стоит читать инструкции?

Прежде всего здесь мы найдем ответы касательно конструкции, возможностей устройства 3Com 10014303, использования отдельных аксессуаров и ряд информации, позволяющей вполне использовать все функции и упрощения.

После удачной покупки оборудования/устройства стоит посвятить несколько минут для ознакомления с каждой частью инструкции 3Com 10014303. Сейчас их старательно готовят или переводят, чтобы они были не только понятными для пользователя, но и чтобы выполняли свою основную информационно-поддерживающую функцию.

Содержание руководства

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    3Com R outer Configuration Guide for V1.20 http://www.3com.com/ Part No. 10014303 Published Janu ary 2004[...]

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    1.1. Intr oduction 1.1.1. Scope This manual provide s configuration inform ation for new software features foun d in V1.20 of the 3Com Router ope rating system. Use thi s addendum to supplement configuration in formation foun d in the 3Com Router Configuration Guide . 1.1.2. Online Re sources Download the Ro uter 3000 Installati on Guid e from: htt[...]

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    Chapter 1 Configuring Class-Based Queuing As an extension of WFQ, class based queui n g (CBQ) provides users with class definition support. CBQ assigns individual FIFO re servation queues to the classes defined by each user to buffer dat a of the same class. Whe n there is network congestion, CBQ matches outbound p ackets a ccording to the classifi[...]

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    policing upon cong estion. If no congestion occurs, the pri ority class is permitted to use bandwid th exceeding the a ssigned val ue. In case of congestion, pa ckets exceeding the assigne d bandwidth of the priori ty class will be disca rded. Burst size is also configurable under LL Q. When the system matches packet s with rules, it matches prior [...]

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    Table 1-2 Define/delete the rule matching all packets Operation Command Define the rule ma tching all pack ets if-match [logic-n ot ] any Delete the rule ma tching all pack ets undo if-match [logic- not ] an y 2) Define the class matching rule Perform the following configuration s in class view . Table 1-3 Define/delete the class matching rule Oper[...]

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    The matching rules of the source MAC address are only meaningf ul for the policies in inbound direction and the interface of Ethernet type. 5) Define the inbound interface matching rule of a class Perform the following configuration s in class view . Table 1-6 Define/delete the inbound interface matching rule of a class Operation Command Define the[...]

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    Use the corresponding command to co nfigure the value of ip precedence duri ng the configuration; otherwise, the configuration of the if-match ip pre cedence command will overwrite the prev ious configurations. 8) Define the RTP port matc hing rule Perform the following configuration s in class view . Table 1-9 Define/delete RTP port matching rule [...]

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    Perform the following configurat ions in the system view . Table 1-12 Define the policy and enter the policy view Operation Command Define the policy and enter the policy view qos policy policy-name Delete the specifi ed policy undo qos poli cy policy-name If an interface applies this policy , this policy is not allowed to b e deleted. Y ou must re[...]

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    configured with a maximum band width, the sy stem will assign the cla ss an individual queue, called the default queue. Theoretically , each class can be configured with bandwid th of any size, but generally , the priority classes can occ upy 70% of the total bandwidth, and other ordinary classes and the default class occupy less t han 10%. It shou[...]

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    3) Configure the maximum queue length of the class Configure maximum queue len gth of the cl ass and co nfigure the drop type as t ail drop. Perform the following configuratio n s in the poli cy-class view . Table 1-16 Configure the maximum queue length of the class Operation Command Configure the max imum queue leng th of the class queue-length qu[...]

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    Table 1-18 Configure exponential of average queue length calculated by WRED Operation Command Configure expone ntial of average queue length calculat ed by WRED wred weighting-constant exponent Delete the configu ration of exponen tial of average queue le ngth calculated by WRED undo wred weig hting-constant This command can be used only af ter the[...]

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    The discarding mode ba sed on WRED mu st already have been en abled via the wr ed ip-precedence command. When the configuration of qos wred is deleted, the wred ip-precedence is also deleted. When the af configuration is deleted, the configuration of discarding p arameters will also be deleted. 8) Enable/Disable traffic policing Perform the followi[...]

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    If qos gts is used in the class-policy that is app lied to the interface, it can o nly be applied to the outbound interface. When the class including T S is applied to the interface, the original qos gts command that is configured on the in terface will become invalid. If this command is repeatedly executed to co nfigure the same class policy , the[...]

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    The following is the rule for a policy to be applied in interface view .  A policy configured with vari ous features (including remark , car , gts , af , ef , wfq , and wr e d ,) a pply to a common physical interface and a virtual template interface over MP.  The policy configured wit h TS (gts), and ef, af, wfq cannot be applied on the inter[...]

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    In terms of service, service flow 1 must occupy a b andwidth of 10K, service flow 2 must occupy a bandwidt h of 20K, under t he premise of ensuring voice service. 10.1.1.1/24 E0 1.1.1.2/24 E0 1.1.4.2/24 Router A Router B s0 1.1.6.1 s0 1.1.6.2/24 1.1.1.1/24 PC 2 PC 1 PC 3 PC 4 Te l e phone Te l e ph on e E1 10.1.1.2/24 E1: 10.1.4.2/24 10.1.4.1/24 1.[...]

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    [RouterA-qosclass-voip] if-match rtp start-port 16384 end-port 32767 [RouterA-qosclass-voip] quit 5 Configure CBQ policy: [RouterA] qos policy 1 6 Configure the bandwid t h of service 1 to be 10K: [RouterA-qospolicy-1] qos-class 1 [RouterA-qospolicy-c-1 1] af bandwidth 10 [RouterA-qospolicy-c-1 1] quit 7 Configure the bandwid t h of service 2 to be[...]

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    Chapter 2 Configuring TACACS+ T ACACS+ is facilitated wit h AAA to control PPP , VPDN, and login ac cess to routers. CISCO ACS is the only applicatio n softwa re that is supported. Compared to RADIUS, T ACACS+ features more reliable transmissi on and encryption, and is more suit able for security control. The following t able list s the primary dif[...]

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    2.2 The Basic Message Inte raction Flow of TACACS+ For example, use T ACACS+ to implement AAA on a telnet user , and the basic message interaction flow descri bed below is used: 1) A user requests access to the rout er . The router(T ACACS+ client) sends t he authentication sta rt packet to the T ACACS+ server upon receipt of the request. 2) The T [...]

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    Us e r HW T A CA C S C lien t HW T ACA C S Se r v e r U s er logs in A u th e n ti c a ti o n S t ar t Re q u e s t p a c k e t A uth en tic a ti o n r es p ons e pa c k e t, req ues ti ng f or th e us e r nam e R e q u e s t U s e r fo r th e u s er n a m e U s er ent er s t he u s er nam e A uth en tic a ti on c o n ti n ua nc e p ac k e t c ar r[...]

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     Standby/Primary server switchover interval  The shared key for the AAA negotiati on between the r outer and TACACS+ Server  Set the timeout time waiting for a TACACS+ server to make a resp onse  Specify a source IP address for all t he TA CACS + packets to be transmitted 2.4.1 Create a TACACS+ server group Before a T ACACS+ server can [...]

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     Note: When this command is used without being configured with the parameter shared-key key-string for negotiation, the default key configured using the shared-key command will be used. 2.4.3 Standby/Primary Se rver Switchover Interval If you have specified the primary and st andby servers in a T ACACS+ server group, the router regularly test s [...]

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    Caution: 1) The entered key must match the key used by the TACACS+ server. 2) All the leading spaces and ending spaces in a key string will be ignored. In addition, a key that contains spaces in the middle is not supported. 2.4.5 Specify a Source IP Address for the TACACS+ Packets to be Transmitted Y ou can specify a source IP address for the T ACA[...]

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    2.5 Displaying and Debugging TACACS+ Execute the following commands in all views. Table 2-7 Display and debug AAA and RADIUS Operation Command Display all the ac counting detai ls. display hwtacacs accounting [ verbose ] Display all the router-TACACS+ interaction de tails. display hwtacacs server [ verbose ] Clear all the accounting d etails. reset[...]

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    2 Configure “mykey” as the shared key for the AAA negotiation with the T ACACS+ server . [3Com-HWTACACS-tactemplate1] shared-key mykey [3Com-HWTACACS-tactemplate1] quit 3 Enable AAA. [3Com] aaa-enable 4 Implement authentication on telnet login use r s. [3Com] login telnet [3Com] aaa authentication-scheme login login-authen-list template tactemp[...]

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    [3Com-serial0] quit 12 Assign an IP add re ss to the interface Ethernet0. [3Com] interface ethernet 0 [3Com-ethernet0] ip address 10.110.1.10 255.255.0.0 13 Assign an IP add re ss to Ethernet1. [3Com-ethernet0] interface ethernet 1 [3Com-ethernet0] ip address 192.10.1.1 255.255.255.0 [3Com-ethernet0] return 2.6.2 Integrating TACACS+ and RADIUS In t[...]

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    [3Com-HWTACACS-tactemplate1] shared-key mykey [3Com-HWTACACS-tactemplate1] quit 5 Configure the IP address, authentic ation port, and acco unting port on the RADIUS server . [3Com] radius server 10.110.1.2 6 Configure the key , retransmission time s, and the timeout time for the RADIUS server . [3Com] radius shared-key my-secret [3Com] radius retry[...]

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    13 Apply the default scheme for ac counting on telnet login use r s. [3Com] login-method accounting-mode login telnet default 14 Enable accounting on Serial0, and conf igure and apply the default accou nting scheme. [3Com] aaa accounting-scheme ppp default radius template tactemplate1 [3Com] interface Serial0 [3Com-Serial0] link-protocol ppp [3Com-[...]

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    Chapter 3 Configuring SSH Terminal Service Secure Shell (SSH) is a feature that p rov ides information about security and powerful authentication functions, whic h can protect a router from the att a cks such as IP address spoo fing and plain text p assword. This is especially evident for remote users who access the router from a nonsecure network [...]

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    T o set up a secure and au thenticated SSH conne ctio n, the server and client must go through the communication procedure t hat fa lls into five stages; version negoti ation, key algorithm negotiation, authentica tion type negotiation, session reques t, and session inte r action. 3.1 Configuring SSH The basic configuration of SSH is required for t[...]

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    Table 3-2 Configure and destroy RSA key-pairs Operation Command Generate RSA key-pairs rsa local-key-pair create Destroy the RSA key-pairs rsa local-key-pair destroy Caution: An essential operation underlying a successful SSH log in is generating local RSA key-pairs. Before performing any other SSH configuration tasks, you must generate a local key[...]

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    Set a server key-pair u pdating interval ssh server rekey-interval hours Restore the defaul t updating interv al undo ssh server rekey-interval By default, the system does not update the server key-p air . Perform this task to set an SSH authenti cation timeout time period. Perform the following confi guration in sy stem view . Table 3-5 Set SSH au[...]

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    when entering key dat a but they will be del eted by the syste m. The configured public key must be a consecutive hexadeci mal char acter string coded in the public key format. Execute the public-key-code end comma nd to stop public key editing and save the key . Before you save the key however , you should verify the validity of the key in case th[...]

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    Perform the following confi guration in sy stem view . Table 3-11 Close SSH processes by force Operation Command Kill SSH process(es ) by force kill ssh { all | userID userid } VI. Display and Debug SSH Information After finishing the configurations de scribed above, view the running st ate of SSH by executing the display commands in all views to v[...]

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     Choose the proper SSH versi on. Genera lly the client provide s several SSH versions. V1.20 supports SSH Server 1 .5, so you must choose 1.5 or lower.  Specify the RSA key file. If you have conf igured to choose RSA authentication a t the server, you must specify the RSA key file at the client. In normal case, RSA key file is created by the [...]

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    III. Choose the SSH version Click “SSH” under “Conn ection” in the left “Category” of the interface, then the following interface appears. Figure 3-2 SSH Client configuration interface (2) S pecify the SSH version to “1”, as shown in the above interfa ce. IV. Enable the SSH connection in p assword authentication mode Click [Open] bu[...]

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    Figure 3-3 SSH Client login interface (in password authentication mode ) After you have entered the correct user name and p assword, you can implem ent the connectio n. T o log out, just use the logout command. V. Enable the SSH connection in RAS authentication mode T o enable the SSH connection in RSA mode, you need to configure the RSA key on bot[...]

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    Figure 3-4 PuTTY Generator Software interface (1) Choose “SSH1(RSA)” o r “SSH2 RSA” as the p arameter and ente r the number of bit s in the key . Click [Generate] button to generate the RSA key . T o ensure the random key , you are required to move the mouse. Once y ou stop moving the cursor , the generating process will pause. After the ke[...]

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    Figure 3-5 PuTTY Key Gen erator interface (2)  Enter a passphrase, if you want to use one.  Save the key After you have generated t he keys, you have an RSA public key and an RSA private key . Click [Save public key] button and [Save pr ivate key] menu to save the keys into files (e.g., publicMyKey .ppk and privateMykey .ppk).  Configure R[...]

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    If you need to perform an RSA authentication, you must specify the RSA private key file. If you only need to perform the passwo r d authenti cation, it is no t nece ssary . Click the “auth” unde r “SSH” in the PuTTY configuration interface and the foll owing figure appears. Figure 3-6 SSH Client Configuration interface (3) Click [Browse] bu[...]

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    Figure 3-7 SSH Client login interface (in RSA authentication mode) After you have entered the correct username , you can perform the SSH co nnection. If a passphrase was u sed when gener ating the keys, the p assphrase is also re quired before a successful SSH connection can be achieve d.  Note: The key generator may be different, depending on t[...]

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     N o t e : If a local key-pair exists, you can omit this step.  Authenticate login users with the password approach [3Com] protocol inbound ssh 5 [3Com] local-user client001 service-type operator ssh password simple 3Com [3Com] ssh user client001 authentication-type password Y ou can adopt the default SSH authentication timeout time, retry ti[...]

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    Chapter 4 Configuring NTP As provisioned in RFC1305, Network T ime Prot ocol (NTP) is a protocol of the TCP/IP suite, which is used to synchronize the timekeepi ng among a set of distributed time servers and client s o n a network. The transmission reli es on UDP . Ne t w o r k Ne t w o r k NT P me ssa g e 10: 00 : 00a m Ne t w o r k Ne t w o r k 1[...]

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     Upon the departure of the NTP mess age, Router B adds its timestam p 11:00:02am (T 3 ) again.  Upon the receipt of the respo nse, Rout er A adds a new timestamp, that is, 10:00:03am (T 4 ). In this way , Router A obtains adequate information for calculating two esse ntial parameters. They are:  Roundtrip delay of a NTP message, tha t is, [...]

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     Configure the NTP server mode  Configure the NTP peer mode  Configure the NTP broadcast se rver m ode  Configure NTP broadcast client mode  Configure NTP multicast server mode  Configure NTP multicast client mode I. Configure NTP Server Mode This task sets a remote server as the loca l time server by specifying its address X.X.X.[...]

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    Table 4-2 Configure NTP peer mode Operation Command Configure NTP peer mode ntp-service unicast-peer X.X.X.X [ version number | authentication-key keyid | source-interface { { interface-name | interface-type } interface-number } | priority ] * Disable NTP peer mode undo ntp-service unicast-peer X.X.X.X NTP versi on is in the range of 1 to 3 and def[...]

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    Table 4-4 Configure NTP broadcast client mode Operation Command Configure NTP broadcast clien t mode ntp-service broadcast - client Disable NTP broadcast client mode undo ntp-service broadcast - client This command must be configured on the in terfa ce to be used for receiving NTP broadcas t messages . V. Configure NTP multicast server mode This ta[...]

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    Table 4-6 Configure NTP multicast client mode Operation Command Configure NTP multicast clien t mode ntp-service multicast - client [ X.X.X.X ] Disable NTP multicast client m ode undo ntp-service multicast - client Multicast IP address X.X.X.X default s to 224.0.1.1. This command must be configured on the interface to be used for receiving NTP mult[...]

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    4.2.4 Specify Reliable Key Y ou must specify a key to be a reliable one before it can be u sed for authentication. For example, if two routers w ant to use keyid 1 for a uthentication, both of them must specify it to be a reliable one. Perform the following confi guration in sy stem view . Table 4-9 Specify a key to be a reliable key Operation Comm[...]

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    Table 4-11 Set an external reference clock or the local clock as the NTP master clock Operation Command Set an external ref erence clock or the local clock as the NTP master clock ntp-service refclock-m aster [ X.X.X.X ] [ stratum ] Disable the NTP master c lock setting undo ntp-service refclock-master [ X.X.X.X ] X.X.X.X represents the IP address [...]

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    Table 4-13 Set the right for accessing the NTP services provided by the local router Operation Command Set the right for ac cessing the NTP services provided by the local rout er ntp-service access { query | synchronization | server | peer } acl-number Disable setting th e rights for accessing the serv ices provided by the local rout er undo ntp-se[...]

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    Perform the debugging command in all views to debu g the NTP information. Table 4-15 Display and debug the NTP information Operation Command Display the state i nformation of t he NTP services display ntp-service st atus Display the se ssi ons state of the NTP service maintenance display ntp-service s essions [ verbose ] Display the brief informati[...]

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    4.3.2 ntp-service s ource-interface disable Syn tax ntp-service source-interface disable undo ntp-service source-i nterface disable View Interface view Parameter None Description Using the ntp-service source-inte rface disable command, you can disable an interface to receive NTP messages. Using the undo ntp-serv ice source-interface disable command[...]

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    vers io n : Defines NTP version number . number : NTP version number in the range of 1 to 3. authentication-k eyid : Defines an authenticatio n key . keyid : The key ID carried i n the messages transmitted to the remote serve r , which is in the range of 1 to 4294967295. source-interface : S pecifies interface name . interface-name : Interface name[...]

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    4.3.4 ntp-servi ce unicast-server Syn tax ntp-service unicast-s erver X.X.X.X [ ver sio n number | authentication-keyid keyid | source-interface { interface-name | interface-type interface-number } | priority ] * undo ntp-service unicast-server X.X.X.X View System view Parameter X.X.X.X : IP address of the remote server . vers io n : Defines NTP ve[...]

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    This command declare s that the local time se rver is the remote server spe cified by X.X.X.X . X.X.X.X represents a host a ddress, which must not be a broadcast or multicast address, or the IP address of the reference clock. Configured with this command, the local device is working in client mode and th erefore it is up to the local client to sync[...]

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    Chapter 5 Configuring X2T The X.25 to TCP swit ch (X2T) technology can interco nnect X.25 and IP networks and enables access b etween X.25 and IP hosts. X.25 Te rmi nal IP Host Router X.25 Network TCP/IP Ne twork X.25 LAPB X.25 LAPB Physical Layer Physical Layer Data Link Layer X2T IP Data Link Layer IP TCP TCP Figure 5-1 Typical X2T networking Fro[...]

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     Configure X2T route I. Enabling X.25 Swit c hing Before configuring X2T , yo u must enable X.25 switching. Perform the following confi guration in sy stem view . Table 5-1 Configure X.25 switching Operation Command Enable X.25 switc hing x25 switching Disable X.25 switc hing undo x25 switching 5.2.2 Configuring the Inte rface at the X.25 Networ[...]

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    forwarding route Delete the X.25-to-IP X2T forwarding route undo translate x25 x.121-address 2) Configuring an IP-to-X.25 X2T forwarding route Perform the following confi guration in sy stem view . Table 5-4 Configure an IP-to-X.25 X2T forwarding route Operation Command Configure an IP-to-X.25 X2T forwarding route translate ip ip-address port port-[...]

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    2 Configure the interface at the X.25 network side. [3Com] interface serial 0 [3Com-Serial0] link-protocol x25 dce [3Com-Serial0] x25 x121-address 1111 3 Configure the interface at the IP network side. [3Com] interface ethernet 0 [3Com-Ethernet0] ip address 10.1.1.1 255.255.255.0 4 Configure an X.25 route [3Com] x25 switch svc 2222 interface serial[...]

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    Chapter 6 Configuring Additional ISDN Support ISDN configuration includes the followin g t a sks: • Configuring the ISDN signaling type. • Configuring the negotiation p arameters of ISDN Layer 3. • Configuring the SPID pa rameters of the National (NI) ISDN protocol. 6.1 Configuring ISDN Signaling Type By default, DSS1 signaling is used on ISD[...]

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    Configure the router to become ACTIVE to s tart data ex change before receiving C ONNECT ACK messages. undo isdn waitconnectack Configure the inter val for the Q931 timers isdn q931-timer timer-name time-interval Restore the defaul t interval timers undo isdn q931-timer timer-name ti me-interval The ISDN SETUP message contai ns th e following infor[...]

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    These can optionally be removed from the SETUP m essag e. 6.2.3 ATT 5ESS (Lucent 5E) Table 6-5 Required ATT 5ESS Commands Operation Command Disable the Sendi ng-Complete Information Ele ment in the Setup message undo isdn sending-complete Disable the SETUP ACK mess ages if the receiv ed SETUP messages in data service calls do not carry the cal led [...]

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    Restore the SETUP mes sage. undo isdn ignore llc Configure the router to w ait for CONNECT ACK message replies from the c onnected exchan ge until switc hing to the ACTIVE state. isdn waitconnectack Configure the router to become ACTIVE to s tart data ex change before receiving C ONNECT ACK messages. undo isdn waitconnectack The ISDN SETUP message [...]