Network Vip

Mere perfomance analysis of long-distance DWDM transmission network

At present, our country, to the communication bandwidth, especially the demand for the bandwidth of long distance communication is very large, so domestic every large telecommunication run commercial city, build widely coverd transmitting the intersection of capacity and loud long-distance DWDM transmission network. But because long-distance the intersection of DWDM and transmission network have the intersection of region and large transmitting from long, the intersection of relaying and the intersection of link and many the intersection of grade and characteristic span, once go wrong, especially while transmitting the degradation question of performance, the localization of the problem is with dealing with the difficulty with very great existence, in view of this, the collection of the performance data and analytical work of the performance that must pay attention to the network and run in the daily maintenance work of the long-distance transmission network, in order to find and handle the hidden danger in time, prevent trouble before it happens. Face the same problem in the maintenance work of Shaanxi Province Branch long-distance DWDM transmission network of CHINAUNICOM too. So this text, with will it be August 2008, first class arterial Beijing that our company launch breathe out too west the intersection of wave and the intersection of subsystem and Suide, go to the intersection of Xi’an and sections of mere the intersection of performance and analytical work for example, carry on the discussion to the problems in this respect.

Breathe out too west wave and divide the systematic network structure in Beijing

Breathe out too west wave subsystem and adopt China to only transmit the apparatus for DWDM in Beijing, capacity 32* 10Gbit/s, through Beijing, Hebei, the Inner Mongol, Shanxi and 5 provinces and cities of Shaanxi, among them, within the territory of Shaanxi, light way chief nearly 800km, the network structure is shown as in Fig. 1.

Question appearing

During the will it be July – August 2008, Beijing breathe out too west the intersection of wave and the intersection of subsystem and the intersection of Shaanxi and inside the province paragraph appear, transmit the intersection of performance and question of degradation, some the intersection of form and the intersection of wave and wave a smooth power low, the mere power drops bigger wholly, and one pair of directions decays unbalancedly, although has not produced yard by mistake yet, has caused the trouble, has already formed all hidden danger of transmitting the performance degradation, so, need to go to Xi’an one and carry on all perfomance analysis to this system Suide, look for the reason, the transmission paragraph making a reservation and going wrong.

A mere perfomance analysis from Suide to Xi’an

And test online through the network management system, I have drawn the mere power data going to each relaying paragraph of the segment of Yanan in systematic Suide, with the historical data ‘ Operation data in May of 2008 Compare, can find out: Until Beijing call too west wave, divide systematic Suide in the transmission network of Xi’an, piece is basically identical to present test result and historical data of a mere power in Xi’an with Tongchuan from Suide to Yanan, without too big change, so, can get rid of the possibility with the hidden danger of this two paragraphs; But the difference between present test result and historical data of phase is relatively great from Yanan to Tongchuan, cause all problem paragraph which transmits the performance degradation, make a concrete analysis of it as follows.

1. Accept the direction of Tongchuan in Yanan: Control the channel and only put the wave one and decay greatly. Accept a mere power in Tongchuan to drop by about 5dB, controls the channel mere power to drop by about 10dB in Huang Ling; Fu County charge the intersection of Huang Ling and section and Yanan charge the intersection of Fu County and section, put the intersection of wave and mere the intersection of power and drop-out value of line only and Huang Ling charge the intersection of Tongchuan and mere the intersection of power and drop-out value of section close, controlling the channel mere power drops 5dB separately too. Explain, charge the intersection of Tongchuan and each of direction, show mere the intersection of transmission and performance degradation at the paragraph only in Yanan, it may be that circuit performance drops to cause because of transmitting, or because the website FIU single-board drops to the fine performance of end of TC2 to cause on the way, but since June, successively three circuit troubles have taken place in this paragraph, after the trouble resumes, the whole paragraph has received some influence, so, it is relatively great to transmit the possibility that circuit performance drops.

2. Accept the direction of Yanan in Tongchuan: Only show the wave a mere power and has not basically dropped, every paragraph controls the channel mere power to drop relatively largely, Tongchuan charge Huang Ling, Huang Ling charge Fu County and Fu County charge Yanan control the channel, drop 5- 7dB, prove Huang Ling drops greater performance between Tongchuan in this direction.

Transmit the mere perfomance analysis of the circuit from Yanan to Tongchuan

To show the intersection of transmission and the intersection of circuit and mere the intersection of power and person who decay and most poor to expect the dampening value to go on comparing actually of paragraph only from Yanan to each Tongchuan Table 1. Among them, the data which receive the direction are gathered some, as every website WPA; The data which send the direction are gathered some, as every website WBA.

Deduct the decaying value of mere power of every station FIU single-board 1dB / one from Yanan to Fu County, decaying value of total mere power of piece from Fu County to Huang Ling, namely the single direction deducts 2dB in each paragraph ,It is paragraph this that transmit mere the intersection of power and dampening value actually of circuit.

Having installed RPC with apparatus of piece because from Huang Ling to Tongchuan, its unable test of mere performance, and at present, Tongchuan it charges the intersection of Huang Ling and RPC of direction to be from the intersection of line and state, so Tongchuan it charges data of Huang Ling to be accurate, but Huang Ling charge the intersection of Tongchuan and data of direction can’t explain the the intersection of transmission and the intersection of circuit and smooth power of direction, dampen the situation actually.

Transmit worst computing technology which expects the decaying value of the circuit mere power: According to suggestion of ITU-T, G.652 the intersection of optic fibre and the intersection of circuit and person who decay as 0.25dB/km, include the intersection of optic fibre and piecing, have degree to spare to be inclusive, G.652 optic fibre circuit decaying value is 0.275dB/km; Ring flange meddle in loss value, fetch, design maximum ‘ Includes the end finely to continue 0.5dB / one; FIU single-board is inserted in to loss and fetch the standard value 1dB / one of Huawei Company. The result of calculation is as follows.

From Yanan to Fu County: According to engineering design, transmit the circuit total length 92.7km guide connecting including the optical cable ,Every station amounts to 7 ODF switching end sons on the way, 2 FIU single-boards, expect the decaying value should be: 92.7* 0.275 7* 0.5 2* 1= 31dB.

From Huang Ling to Fu County: According to engineering design, transmit the circuit total length 93.9km guide connecting including the optical cable ,Every station amounts to 6 ODF switching end sons on the way, 2 FIU single-boards, expect the decaying value should be: 93.9* 0.275 6* 0.5 2* 1= 30.82dB.

From Huang Ling to Tongchuan: According to engineering design, transmit the circuit total length 110.5km guide connecting including the optical cable ,Every station amounts to 9 ODF switching end sons on the way, 2 FIU single-boards, expect the decaying value should be: 110.5* 0.275 9* 0.5 2* 1= 36.9dB.

Can find out by Table 1, the same paragraph transmit circuit mere power dampening value relatively loud difference stores in in receiving and dispatching two directions actually: Differ by nearly 6dB from Yanan to Fu County Section; Differ by nearly 5dB from Fu County to Huang Ling Section; Differ by nearly 4dB from Huang Ling to Tongchuan Section.

From Yanan to Fu County Section: The decaying value is superior to the worst expected value actually to accept the mere power of the direction of Yanan in Fu County, Yanan charges the direction of Fu County to transmit the circuit to need to optimize 6dB, reach the decaying value of mere power close to Fu County to accept the direction of Yanan.

From Fu County to Huang Ling Section: The decaying value is superior to the worst expected value slightly actually to accept the mere power of the direction of Fu County in Huang Ling, Fu County charges the direction of Huang Ling to transmit the circuit to need to optimize above 4dB, reach the decaying value of mere power close to Huang Ling to harvest the direction of Fu County.

From Huang Ling to Tongchuan Section: The decaying value is superior to the worst expected value actually to accept the mere power of the direction of Huang Ling in Tongchuan, harvesting the direction of Tongchuan in Huang Ling though can’t test directly, need to accept the direction of Huang Ling to keep with Tongchuan close to.

Rectify and improve and optimize the scheme

According to the above mere perfomance analysis, I have proposed rectifying and improving and optimizing the scheme as follows.

1. Transmit the circuit and rectify and improve and optimize the scheme

To from Yanan to the intersection of Tongchuan and section, arterial optical cable and guide, it answers an optical cable to be here inside, the neighbor beats and stands and transmits the test of the spare fine core of circuit piecemeal according to taking pictures, chase and stand, chase the abnormal mere power existing in exclusion with fine end and chasing and jumping and is clicked and decay, clean the intersection of tail and fine piecing and son, end of switching, completely, find out mere power dampen minimum fine core between the every station, the mere power of the whole paragraph dampens the index and should be in conformity with above-mentioned analysis result, later, arrange in unison, only put section according to the wave subsystem, finish the fine core to connect piecemeal, solve and transmit the problem that the circuit only transmits the performance degradation.

2. The engineering regulates and rectifies and improves and optimizes the scheme

After transmitting circuiting to rectify and improve and optimize, test, clean or change Yanan in the intersection of Tongchuan and piece apparatus end of every website is fine, and regulate the mere index of performance of the apparatus to peak according to above-mentioned analysis data and conclusion.