Learning IOS and JUNOS

Wide area file services (WAFS) products allow remote office users to access and share files globally at LAN speeds over the WAN . Distributed enterprises that deploy WAFS solutions are able to consolidate storage to corporate datacenters, eliminating the need to back up and manage data that previously resided in their remote offices. WAFS uses techniques such as CIFS and MAPI protocol optimization, data compression , and sometimes storing recurrent data patterns in a local cache . WAFS is a subset of WAN optimization , which also caches SSL Intranet and ASP applications and elearning multimedia traffic as well, to accelerate a greater percentage of WAN traffic.

自從接觸了廣域網路加速器這個領域，愈來愈覺得自己對TCP的了解實在是只懂得皮毛而已。原來在TCP上的實現有這麼多種改進方式，使得TCP的傳輸表現更加優越。 以下的內容是節錄自Cisco Press Application Acceleration and WAN Optimization Fundamentals中的章節，由於這幾個協定可以說是各家廣域網路加速器都會參考的標準，用以改善原有TCP設計運作上的缺陷，所以我把它們整理出來加以分較，希望對各位有所幫助! HS-TCP(High Speed TCP) High-Speed TCP is a advanced TCP implementation that was developed primarily to address bandwidth scalability. HS-TCP uses an adaptive cwnd increase that is is based on the current cwnd value of the connection. When the cwnd value is large, HS-TCP uses a larger cwnd increase when a segment is successfully acknowledged. In effect, this helps HS-TCP to more quickly find the available bandwidth, which leads to higher levels of throughput on large networks much more quickly. HS-TCP also uses an adaptive cwnd decrease based on the current cwnd value. When the cwnd value for a connection is large, HS-TCP uses a very small decrease to the connection's cwnd value when loss of a segment is detected. In this way, HS-TCP allows a connection...

．Check License Key: PacketShaper# setup keys show Installed Keys: compatibility 1 control on linksize 2m compression on acceleration on (Expires: 20081002) ．License Upgrade Usage: setup keys add [yyyymmdd] PacketShaper# setup keys add compatibility PacketShaper# setup keys add control PacketShaper# setup keys add linksize PacketShaper# setup keys add compression PacketShaper# setup keys add acceleration ．Measurement Engine(ME) ．Police PacketShaper# ipfilter show Show IP info clear Clear IP filter[s] onlyaccept Only accept specified packets passthrough Passthrough specified packets discard Discard specified packets iponly Relay only IP trafic on|off. ．Show configuration limits PacketShaper# sys limits Statically allocated objects Current Remaining Total -----...

今年Bluecoat併購了一家歷史優久的網路設備商Packeteer，其著名產品可能很多人都有聽過 - PacketShaper，至於為什麼Bluecoat會併購Packeteer，想當然而就是希望1+1大於2效應，兩家產品各有所長，如果可以雙劍合一對網路管理者來說當然是最好不過的事(in-line service大家都不希望看到太多可能的變數)，不過短期內應該仍會是以不同系列的產品來供應市場，也許未來會有更進一步的整合計劃，就讓我們拭目以待! 在這次的Bootcamp中主要的課程內容是以實作為主，所以大部份的時間都是由講師來講解使用上的注意事項及使用經驗分享，對於第一次接觸PacketShaper的人來說有點緊湊，有一個很主要的原因那就是大家手上並沒有講義可以翻閱，有時如果一時失神沒聽到或是沒看到DEMO畫面的話，可能就會不知道剛剛miss掉了那些東西，不過整體來說至少可以對於PacketShaper產品有一個概括的了解，簡單上架設定應該是不成問題。但是如果可能的話，最好還是可以參加比較正式的課程才會有完整性的了解! 以下是小弟那兩天的筆記，不過由於PacketShaper主要是利用GUI畫面來設定，所以小弟的筆記有限只能針對CLI的部份作註記請各位諒解! ．Packetshape Password Recovery 重開機之後，在第一個輸入密碼畫面輸入'touchpwd=' (如果打錯必須再次重開機) ．密碼分為兩個層級： touch 123 (touch level password 123, blank password in default) look 123 (look level password 456, blank password in default) 如果password相同，會使用最高權限level PacketShaper#reset (重開機) PacketShaper#setup reset all (Reset to Factory Default) ．Press Q to skip prompt text ．207.78.98.254 (default IP) ．unconfigured.packeteer.com (default FQDN) PacketShaper#net nic (check interfa...

以下是Set-Cookie中參數TM及LM解釋，引用自Cookie Dethroning.::DEMYSTIFIED(http://www.infosecwriters.com/text_resources/pdf/CookieCorePartA.pdf)這份文章中的說明： Here is an example of a Google cookie: GPREF=ID=26b2149fe108b391:TM=1109736400:LM=1109736400:S=pbbDWyL8tVmJrIL c You can see that after "GPREF=", there are name-value pairs ID, TM, LM, and S (separated by colons). In this case, our ID is 26b2149fe108b391. This is a (hopefully) unique ID, and it is most likely generated randomly. Google probably doesn't worry about "collisions" (two users getting the same ID) because this is a 16-digit hexadecimal number, and there are 16^16 = 18446744073709551616 = 18.44674 x 10^18 possible IDs that could be assigned. Even if everyone on the planet used Google, the chance of collision would be very low. Google's cookie has an expiration date of January 17, 2038. Essentially, unless you purposely clear your cookies, format your hard drive, etc. this means it will be with you for a very long...