Clan Web Sites, Online Games and Hosting

60 Networking and Online Games: Understanding and Engineering Multiplayer Internet Games Tunnelling over an IPv4 network imposes an additional 20 bytes of overhead (the header of the outer IP packet) [RFC2003]. The MTU of the tunnel s virtual link is 20 bytes smaller than the smallest MTU along the outer packet s path. (RFC 2004 suggests a more efficient encapsulation mechanism incurring only 8 or 12 bytes of overhead but with some loss of generality, for example, fragmented IPv4 packets cannot be tunnelled [RFC2004]. For RFC2004-based tunnelling, the protocol type in the encapsulating/tunnelling header is 55.) When tunnelling over IPv6 networks, the MTU drops by at least 40 bytes (the size of the encapsulating IPv6 header) [RFC2473]. 4.3 Address Management Every IP interface needs an IP address, which raises some very real administrative issues when building big networks. There are two key aspects to address management: Establishing an IP subnet from which you can assign IP addresses Actually assigning individual IP addresses to interfaces. In this section, we will review how address blocks are assigned to customer networks from blocks delegated to Internet Service Providers (ISPs); how NAT can be used to overcome limitations in ISP address assignments; how the DHCP simplifies address assignment to individual devices inside your networks and how the domain name service attempted to decouple the naming of endpoints from the addressing of endpoints. 4.3.1 Address Delegation and Assignment To be part of the wider Internet you cannot pick a subnetwork number and prefix at random. You need IP addresses that are globally unique and routable on the Internet. Such addresses are typically obtained from your ISP, which assigns you addresses from larger blocks allocated to the ISP by regional registries around the world [RFC2050]. For example, ARIN (the American Registry for Internet Numbers) manages space under 204/8 (204.0.0.0/8) and a number of other large blocks of IPv4 address space, and APNIC (the Asia-Pacific Network Information Center) manages space under 218/8 and a number of other large blocks. An ISP who asks for space from APNIC will receive an allocation under 218/8 or one of APNIC s other address blocks. Regional registries develop their own policies for subdividing the address blocks they manage. Up-to-date information on registries and assignment policies can be found in the Internet Assigned Numbers Authority web site, http://www.iana.org. Problems arise when you decide to change ISPs. You will usually be forced to adopt a new IP address space assigned by your new ISP (called renumbering). Renumbering of your network is usually required by ISPs because routing would become more convoluted if the address hierarchy was allowed to arbitrarily diverge from the hierarchy of actual connectivity among the service providers. A number of IPv4 address blocks (10/8, 172.16/12 and 192.168/16) have been reserved for use in private internets [RFC1918]. These are useful when building IP networks that will never be connected to the Internet, or will be connected only in a very limited fashion. In principle, such IP networks could be built using any prefixes. However, using designated private IP address spaces helps administrators distinguish between internal and

Note: If you are looking for good and high quality web space to host and run your application check Lunarwebhost Inexpensive Web Hosting services