WAN code management

There is no WAN code management tool ? Kind of like clearcase or svn . The development there may not be present in the same domain , nor the same LAN . How the code synchronization management ?
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try for free and supports proprietary library code hosting site , such as bitbucket.org , etc. , you can own search.
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VSS, CVS and SVN offer Web-based interface , users can perform configuration management through a browser -related operations , that is, through such methods to achieve offsite development support. But relative to the CVS, SVN unified binary differencing algorithm , so consume less network bandwidth and therefore more suitable for Internet-based ( or WAN ) to collaborate on the development of geographically distributed teams , namely centralized server version , single ; client can widely distributed .
In fact the method has too many limitations, such as a network (Internet) connection bandwidth limitations , firewalls and security issues . Truly offsite development support , refers to the different development sites to establish their own repository synchronization tool provides functionality through automatic or manual synchronization . This benefit has nothing to do with the network , even if the individual is no real-time connectivity between the development site network , you can also E-Mail attachments and other ways to sync packets to each other, to achieve manual synchronization. The ClearCase able to achieve such functionality.
worthy of note that, in the different development points the way to establish their own repository , mainly applicable to two or more development teams in different locations collaborative development situation. If only the virtual teamwork approach , developers in the form of individuals scattered in different places , is more suitable for remote operation via the Internet directly to the configuration management server.

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You said just put the code hosting site is on top, then you can download it ? What I need is a checkout, checkin kind , checkout to be locked and can not be modified.
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Thank you ! Relevant information has been found !
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Will withheld , what method you use to solve ? I recently needed to develop and remote students , but no way to manage code. Please advise the most grateful .
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Will withheld , what method you use to solve ? I recently needed to develop and remote students , but no way to manage code. Please advise the most grateful .  
use Github. CSDN the CODE is also good , try it