The Research Of The MAN Construction And The Application Of Broadband Access Technology In CRNet

In recent years, the broadband data city territory netconstruction was on the rising among. Many telecommunicationoperations positively invested and raised ,which has seized thehigh tide of the last kilometer. At the same time along with Internetin multi-domains application and swift and violent developmentPeople also set a higher request to the network bandwidth and thehigh speed, which urges the network to be high speed from the lowspeed, from shares to the exchange, rapidly develops by the narrowband to the broadband direction. In order to adapt the new marketsituation and the need, The many kinds of broadband access thetechnology to arise at the historic moment, turns on the technology,the optical fiber including the copper wire turns on the technology,hybrid fiber coax (HFC) turns on the technology and so on many kindsof wired to turn on the technology as well as wireless turns on thetechnology and so on. But the market has own rule, expends demand is the decisivefactor. The tietong company took emerging telecommunicationoperation business, certainly needs to profit from other operationbusiness in the city territory broadband data networkingconstruction the experience. In the city territory broadband datanetworking take the market demand as the guidance, according to eachplace concrete economical development situation, the existingnetwork resources, the service demand and the operation businessmarket competition situation determination city territory netconstruction plan, selects the corresponding broadband accesstechnology. This paper bases on the actual situation of Tietong company,which the broadband data city territory net constructs, focuses innow the city territory net market and the broadband technologydevelopment, had expounded the iron passes the city territory netin construction basic skeleton the technical orientation, thenetwork construction principle and the network level whichconstructs including its city territory net. Which technologiesstudies and narrates the present broadband access the technologyand its suits in the iron passes in the city territory netconstruction to apply. The discussion and constructed the iron topass the broadband data networking initially to set up the way, theiron will pass the city territory net by the time to current andthe next certain time in the construction and its the broadbandtechnology application provides the certain reference.At present the market user to the broadband data service demandconclusion is two big kinds: A kind is has the strict request toQoS the highgrade service;another kind is pursues the highefficiency large capacity based on the IP service. Passes the cityterritory net according to the present iron the user localizationof target, the iron passes should mainly locate the user goal onthe big enterprise group users, but regarding individual, thefamily plot accesses the net the primarily service by the broadbandto be supposed to have the key gradually development, therefore theiron suitably passes the city territory broadband data networkingfirst to construct based on the ATM multi-services platform, isproviding many kinds of grade of service has the guarantee service---the frame to relay FR/Special line DDN/ATM ---but at the sametime the load bearing IP service and carries on the ADSL servicegathering. Develops in the city territory net to the certain stage,passes the Internet service along with the iron the graduallydevelopment, may again construct based on the IP platform, providesthe omni-directional telecommunication service for the cityterritory net user.The question of broadband access has the many kinds of plansto be possible to solve, for instance DDN technology, xDSLtechnology, HFC technology, ethernet technology and so on. Amongthem, the xDSL technology is one kind compares successful and themature technology. Certainly also has the ethernet technology andso on large quantities of broadbands technologies the applicationto develop with steady steps.At present the broadband access technology may use in thetietong company include: The special line turns on the technology,the ADSL technology, the VDSL technology, and the ethernet, Cablethe Modem system as well as the local multi-spots distributionsystem (LMDS). The turning on technology that suits the tietongcompany to use include: The DDN special line turns on the technology,ADSL and VDSL turns on the technology, the ethernet and so on.In the initial construction period of the city territory net,we mainly face some big and middle enterprises users. And provideeach kind of telecommunication service, can have the very highrequest to the network quality, by now came the network through theATM technology, and might fully display the ATM technology exactlyto have the very good QoS guarantee the superiority.These enterprise users turn on directly to the iron pass thecity territory net the gathering level, using special line DDN, theframe relaying, ATM or VPN and so on constructs the enterpriseinterior Internet Intranet, realizes the electronic commerce forthe enterprise to provide the possibility;Moreover the enterprisealso may pass Internet CRNet through the iron to turn on the internet,by obtains the newest market information, brings the income for theenterprise.In the construction of the city territory net of tietong, thefull use and the excavation iron pass already the copper wireresources which has, positively develops the ADSL broadband accessthe service, at present the iron passed many areas all to disposeADSL to turn on the equipment, should increase the ration in thisfoundation DSLAM to turn on the equipment, is connected by theseequipment to the ATM multi-services city territory net on, anddelivered the broadband after the ATM switchboard current capacitygathering to turn in the server, the broadband turned on the serverto provide the user the authentication, to cost and the incrementservice (firewall, address translation, user speed limitation,service wholesale and hypothesized special-purpose net VPN), thenturned on to the iron passes on the backbone Internet, Provides theInternet to turn on the service.The VDSL technology took one of ADSL technology developmentdirections, is at present most advanced digital subscriber linetechnology, uses this technology to be possible further to enhancethe xDSL system the under good band width.The VDSL technology usually selects the DMT modulation method andis separated the young Pood frequency modulation (DWMT), DWMT hasused the wavelet orthogonal transformation, and therefore theperformance is better than DMT. All concentrates after abovewavelet transformation DWMT sub-channel power 99% in the main lobe,thus the signal to noise ratio obtained the big enhancement.Although the VDSL effective transmitting range is slightlyshorter than ADSL, but looked from the present situation, thereforethe current goal is realizes the optical fiber first to the roadside(FTTC) or the optical fiber to the building (FTTB), therefore oncethese two plans obtain the widespread application, VDSL maymassively use in the building interior office or connection betweenthe plot family.Regarding ethernet user's turning on, usually is lays aside theethernet switchboard or HUB in the user plot apartment building evenentry, uses five kind of comprehensive wiring to enter in the userresidence each room to turn on. User connects which regarding theethernet, may use VLAN or the PPPoE way carries on theauthentication to these users, costs.Along with the broadband service development, a new concept,the BAS broadband access the server to arise at the historic moment,the broadband access the server in the network gathering leveldeployment, uses in the high intellectualization realizing theentire net user gathering, the authentication, costs with incrementprovision of service.Turns on the server based on the broadband, the iron passes maywhile provide the user to turn on the gathering function to turnon the user, provides each kind of rich IP increment service, likethe firewall, the address translation, the user speed limitation,the truing, filter, forces the gateway, hypothesizedspecial-purpose net VPN and so on, this turns on in the profit moreand more low situation regarding the operation business in atpresent, continues to maintain the good income development isextremely advantageous.Actual sets up the broadband networks system to have many ways,under passed the Jilin subsidiary company broadband net on the ironthe network to carry on the broadband access the way the comparison,the iron passes the company broadband network system to use threestructures roughly: The backbone level, turns on the level, the userlevel. Selects what method regarding user itself to turn on, shouldsynthesize the actual each kind of demand and the condition carrieson the comparison, and chooses the appropriate way.Considered passes the Jilin Province subsidiary company to theiron the city territory net service development needs in ten placescities development broadband service. At present only then sixcities have the iron to pass the broad-band multi-services datanetworking the pitch point, must also provide the city territorynet service in other cities, first must expand the existing ironto pass the province net the scale and the festival points,increases four subsidiary companies pitch points in the originalfoundation.For some key cities like Changchun, considered to its servicedevelopment, may set up certain cores pitch point in the servicecentralism pitch point. And the full use had the Tietong Companythe multi-services data backbone network the equipment;moreoverthe suitable increase core gathers the ATM switchboard.