Measurements such as Insertion Loss, NEXT and Return Loss are referred to as “swept frequency” measurements, meaning that certain points between the minimum and maximum frequency of the selected test standard are measured. It goes with out saying that if you only measure 100 points between 1 MHz and 1,000 MHz – it will make for a very quick test, but fail to provide the desired resolution.
插入損耗、NEXT和回波損耗的測量被稱為“掃頻”測量,這意味著測量所選測試標(biāo)準(zhǔn)的最小和最大頻率之間的某些點。不用說,如果你在1Mhz到1000Mhz之間只測量100個點-他就會測試速度非??欤遣荒芴峁┧璧姆直媛?。
So the field testing standards ANSI/TIA-1152 and IEC 61935-1 define the minimum frequency steps (resolution) for the test equipment vendors.
ANSI/TIA-1152
IEC 61935-1 Ed.4
The DSX2-8000、DSX2-5000 provides better resolution than the minimum required for IEC 61935-1 Ed.4. It is worth investigating what resolution your vendor is using.
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NETSCOUT Linkrunner G2(LRG2)網(wǎng)絡(luò)測試儀視頻操作培訓(xùn)
Linkrunner G2產(chǎn)品詳細(xì)介紹:http://www.faxy-tech.com/Products/LR-G2.html
NETSCOUT LRAT-2000、LRAT-1000產(chǎn)品視頻操作:
NETSCOUT Linkrunner AT:http://www.faxy-tech.com/Products/NT-LRAT.html
深圳連訊達(dá)對NETSCOUT 1TG2-1500/1TG2-3000進(jìn)行了簡單視頻介紹。有其他報價或者技術(shù)問題聯(lián)系:400-966-0787
包括:
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通過端對端的路徑性能評估,確保新安裝或升級的有線和 Wi-Fi 網(wǎng)絡(luò)達(dá)到 SLA 目標(biāo),并且能夠滿足新的更高帶寬的應(yīng)用程序的需要。評估本地 OneTouch AT 和遠(yuǎn)端 OneTouch AT 對等設(shè)備或遠(yuǎn)端 LinkRunner 或 NPT Reflector 軟件等反射器間的吞吐量、丟幀、延遲和抖動。遠(yuǎn)端對等設(shè)備提供上行和下行的結(jié)果,而遠(yuǎn)端反射器提供往返的結(jié)果。OneTouch AT G2 根據(jù) RFC2544 算法在銅線和光纖網(wǎng)絡(luò)上評估速率達(dá)到 1 Gbps 時的性能,在 Wi-Fi 網(wǎng)絡(luò)上評估速率達(dá)到 600 Mbps 時的性能。OneTouch 10G 可根據(jù) Y1564 相對其他 OneTouch 10G 對等設(shè)備評估高達(dá) 10Gbps 時的網(wǎng)絡(luò)性能。OneTouch 也可使用任意 iPerf v3.x 服務(wù)器或 NETSCOUT TEST-ACC 通過 Wi-Fi 或有線網(wǎng)絡(luò)執(zhí)行 iPerf 測試。它最合適在故障排除時評估 TCP 流可達(dá)到的最大吞吐量或 UDP 流的網(wǎng)絡(luò)性能。
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在 Internet上,各主機(jī)間通過TCP/TP協(xié)議發(fā)送和接收數(shù)據(jù)報,各個數(shù)據(jù)報根據(jù)其目的主機(jī)的ip地址來進(jìn)行互聯(lián)網(wǎng)絡(luò)中的路由選擇??梢姡褦?shù)據(jù)報順 利的傳送到目的主機(jī)是沒有問題的。問題出在哪里呢?我們知道大多數(shù)操作系統(tǒng)都支持多程序(進(jìn)程)同時運行,那么目的主機(jī)應(yīng)該把接收到的數(shù)據(jù)報傳送給眾多同 時運行的進(jìn)程中的哪一個呢?顯然這個問題有待解決,端口機(jī)制便由此被引入進(jìn)來。
本地操作系統(tǒng)會給那些有需求的進(jìn)程分配協(xié)議端口 (protocal port,即我們常說的端口),每個協(xié)議端口由一個正整數(shù)標(biāo)識,如:80,139,445,等等。當(dāng)目的主機(jī)接收到數(shù)據(jù)報后,將根據(jù)報文首部的目的端口 號,把數(shù)據(jù)發(fā)送到相應(yīng)端口,而與此端口相對應(yīng)的那個進(jìn)程將會領(lǐng)取數(shù)據(jù)并等待下一組數(shù)據(jù)的到來。說到這里,端口的概念似乎仍然抽象,那么繼續(xù)跟我來,別走 開。
端口其實就是隊,操作系統(tǒng)為各個進(jìn)程分配了不同的隊,數(shù)據(jù)報按照目的端口被推入相應(yīng)的隊中,等待被進(jìn)程取用,在極特殊的情況下,這個隊也是有可能溢出的,不過操作系統(tǒng)允許各進(jìn)程指定和調(diào)整自己的隊的大小。
不光接受數(shù)據(jù)報的進(jìn)程需要開啟它自己的端口,發(fā)送數(shù)據(jù)報的進(jìn)程也需要開啟端口,這樣,數(shù)據(jù)報中將會標(biāo)識有源端口,以便接受方能順利的回傳數(shù)據(jù)報到這個端口。
Network ports are the entry points to a server or workstation that is connected to the Internet. A service that listens on a port is able to receive data from a client, process it and send a response back. Malicious clients can sometimes exploit vulnerabilities in the server code so they gain access to sensitive data or execute malicious code on the machine remotely.
The Port Scan feature scans the target device for many commonly used open ports. Results are reported on the device’s button on?the WIRED ANALYSIS screen. The device’s button must be expanded to view the port scan results.
To use the Port Scan?feature:
What ports are scanned?
OneTouch AT G2scans the following ports during the “PortScan” process.? OneTouch AT does not scan all ports in order to prevent tripping an IDS/IPS system.
7 | echo | 554 | rtsp | |
9 | discard | 556 | remotefs | |
11 | systat | 585 | imap | |
13 | daytime | 634 | ginad | |
17 | qotd | 636 | ldaps | |
18 | msp | 666 | doom | |
19 | chargen | 749 | kerberos-adm | |
20 | ftp-data | 762 | quotad | |
21 | ftp | 892 | ||
22 | ssh | 901 | snmpnameres | |
23 | telnet | 902 | vmware-console | |
25 | smtp | ………… | 912 | apex-mesh |
37 | time | 993 | imaps | |
38 | rap | 995 | pop3s | |
39 | rlp | 1025 | microsoft-adl | |
43 | nicname | 1080 | socks | |
49 | tacacs | 1155 | nfa | |
53 | domain | 1366 | netware-csp | |
66 | sql-net | 1417 | timbuktu-srv1 | |
67 | bootps | 1433 | ms-sql-s | |
68 | bootpc | 1434 | ms-sql-m | |
70 | gopher | 1498 | sybase-sqlany | |
79 | finger | 1521 | oracle-db | |
80 | http | 1524 | ingreslock | |
88 | kerberos | 1525 | orasrv | |
107 | rtelnet | 1720 | h323hostcall | |
110 | pop3 | 1723 | pptp | |
111 | sunrpc | 1812 | radius | |
113 | ident | 1813 | radius-acct | |
118 | sqlserv | 2000-2002 | cisco-sccp | |
123 | ntp | 2049 | nfs | |
135 | epmap | 3128 | ndl-aas | |
137 | netbios-ns | 3268 | msft-gc | |
138 | netbios-dgm | 3269 | msft-gc-ssl | |
139 | netbios-ssn | 3306 | mysql | |
143 | imap | 3389 | ms-wbt-server | |
156 | sqlsrv | 4400 | ds-srv | |
161 | snmp | 4488 | awacs-ice | |
162 | snmptrap | 4672 | rfa | |
204 | at-echo | 4899 | radmin-port | |
379 | ldap | 5190 | aol | |
389 | ldap | 5432 | postgresql | |
390 | ldap | 6000-6004 | ms-exchange | |
427 | svrloc | 6005 | x11 | |
443 | https | 8001 | http-alt | |
445 | microsoft-ds | 8080 | http-alt | |
465 | urd | 8443 | pcsync-https | |
512 | exec | 12345 | italk | |
513 | login | 50000 | db2-server-old | |
514 | shell | 60000 | db2-server | |
515 | printer | 62078 | iphone-sync | |
519 | utime |
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