IPv6 Explained

Internet Protocol (IP)

IP (short for Internet Protocol) specifies the technical format of packets and the addressing scheme for computers to communicate over a network. Most networks combine IP with a higher-level protocol called Transmission Control Protocol (TCP), which establishes a virtual connection between a destination and a source. It allows you to address a package and drop it in the system, but there's no direct link between you and the recipient. TCP/IP, on the other hand, establishes a connection between two hosts so that they can send messages back and forth for a period of time.

Why do we need IPv6?

New network devices that require IP addresses are on the rise. An example is a single user with a laptop, smartphone, a PC and a netbook. These are four public IPs if the person has to connect with a static IP with no NAT. Multiply that with the population that owns or are planning to acquire these devices.

NAT (Network Address Translation) is seen as an obstacle to innovation; therefore, we are shifting focus to a generation where we require mobility as well as security and a version of IP addresses that will support the next generation of devices

Internet Protocol Version 6 (IPV6)

Internet Protocol version 6 (IPv6) is a network layer for packet-switched internetworks. It is designated as the successor of IPv4, the current version of the Internet Protocol, for general use on the Internet.

The main change brought by IPv6 is a much larger address space that allows greater flexibility in assigning addresses. The extended address length eliminates the need to use network address translation to avoid address exhaustion, and also simplifies aspects of address assignment and renumbering when changing providers. It was not the intention of IPv6 designers, however, to give permanent unique addresses to every individual and every computer.

Features and differences from IPv4

The main features of IPv6 that is driving adoption today are listed below.

• Larger address space (addresses in IPV6 are 128 bits long)
• No more NAT (Network Address Translation)
• Auto-configuration
• No more private address collisions
• Better multicast routing
• Simpler header format
• Simplified, more efficient routing
• True quality of service (QoS), also called "flow labeling"
• Built-in authentication and privacy support
• Flexible options and extensions
• Easier administration (say good-bye to DHCP)

IPv6 Addresses

The primary change you can notice in IPV6 is increasing the size of IP addresses from 32bits to 128 bits change from IPv4 to IPv6 is the length of network addresses. IPv6 addresses are 128 bits long. IPv4 address space contains roughly 4 billion addresses, IPv6 has enough room for 3.4×1038 unique addresses.

IPv6 addresses are so much larger than IPv4 addresses that even using dotted decimal notation becomes problematic. To make addresses shorter, the decision was made in IPv6 to change the primary method of expressing addresses to use hexadecimal instead of decimal. The advantage of this is that it requires fewer characters to represent an address, and that converting from hex to binary and back again is much easier than converting from binary to decimal or vice-versa.

IPv6 addresses are normally written as eight groups of four hexadecimal digits, where each group is separated by a colon (:).

A typical IPv6 address in this notation would appear as follows:

Example: 2001:0DB8:0000:0000:0000::1428:57AB is a valid IPv6 address.

To keep size down, leading zeroes can be suppressed in the notation, so we can immediately reduce this to:

2001:0DB8:0:0:0:1428:57AB

or

2001:0DB8::1428:57AB

or

2001:DB8::1428:57AB

Note: Having more than one double-colon abbreviation in an address is invalid

Network Prefixes

IPv6 pool and are divided into two parts, a network section and a host section. The network section identifies the particular network and the host section identifies the particular node for example, a certain computer on the Local Area Network

Allocation

IPv6 networks are written using CIDR (Classless Inter Domain Routing) notation. similar / (forward slash) notation to IPv4 CIDR) which describes the number of contiguous bits used in its netmask. which shows the number of IP addresses contained in that block.  Formally this way of writing an address is called an IP prefix but more commonly called the slash format.

For example 2001:0db8:1234::/48 if an Internet Service Provider (ISP) is assigned a “/26” network provides 64 IPv4 addresses. The lower the number after the slash(/), the more addresses contained in that “block”.

An IPv6 network (or subnet) is a contiguous group of IPv6 addresses the size of which must be a power of two; the initial bits of addresses, which are identical for all hosts in the network, are called the network's prefix.

IPv6 Relative Network Sizes

Kinds of IPv6 addresses

IPv6 addresses are divided into 3 categories

• Unicast Addresses – One to One
• Multicast Addresses – One to Many
• Anycast Addresses – One to Closest

Unicast

Identifies a single interface within the scope of the address. (The scope of an IPv6 address is that portion of your network over which this address is unique.) IPv6 packets with unicast destination addresses are delivered to a single interface.Global unicast addresses

• Link-local addresses
• Site-local addresses
• Unique local IPv6 unicast addresses
• Special addresses

Multicast

In IPv6 is similar to the old IPv4 broadcast address a packet sent to a multicast address is delivered to every interface in a group. The IPv6 difference is it's targeted instead of annoying every single host on the segment with broadcast blather, only hosts who are members of the multicast group receive the multicast packets. IPv6 multicast is routable, and routers will not forward multicast packets unless there are members of the multicast groups to forward the packets to. Anyone who has ever suffered from broadcast storms will appreciate this mightily.Multicast addresses begin with the prefix FF00::/8, and their second octet identifies the addresses' scope, i.e. the range over which the multicast address is propagated. Commonly used scopes include link-local (0x2), site-local (0x5) and global (0xE).

Anycast

Identifies multiple interfaces. IPv6 packets with anycast destination addresses are delivered to the nearest interface (measured by routing distance) specified by the address. Currently, anycast addresses are assigned only to routers and can only represent destination addresses.

Special addresses

There are a number of addresses with special meaning in IPv6:

Link local

::/128 – Unspecified This address may only be used as a source address by an initializing host before it has learned its own address.

::1/128 – Loopback This address is used when a host talks to itself over IPv6. This often happens when one program sends data to another.

fe80::/10 - These addresses are used on a single link or a non-routed common access network, such as an Ethernet LAN. They do not need to be unique outside of that

Link-local addresses may appear as the source or destination of an IPv6 packet. Routers must not forward IPv6 packets if the source or destination contains a link local address.

Link-local addresses may appear as the source or destination of an IPv6 packet. Routers must not forward IPv6 packets if the source or destination contains a link local address.

Site local

fc00::/7 Unique Local Addresses (ULAs) These addresses are reserved for local use in home and enterprise environments and are not public address space. These addresses might not be unique, and there is no formal address registration. Packets with these addresses in the source or destination fields are not intended to be routed on the public Internet but are intended to be routed within the enterprise or organization.

IPv4 Mapped

 ::ffff:0:0/96 These addresses are used to embed IPv4 addresses in an IPv6 address. One use for this is in a dual stack transition scenario where IPv4 addresses can be mapped into an IPv6 address. See RFC 4038 for more details.

2002::/16 - this prefix is used for 6to4 addressing.

Multicast

• ff00::/8 - The multicast prefix is used for multicast addresses as defined by in "IP Version 6 Addressing Architecture" (RFC 4291).

Used in examples, deprecated, or obsolete

• ::/96 - the zero prefix was used for IPv4-compatible addresses; it is now obsolete.
• 2001:db8::/32 - this prefix is used in documentation (RFC 3849). Anywhere where an example IPv6 address is given, addresses from this prefix should be used.
• fec0::/10 - The site-local prefix specifies that the address is valid only inside the local organization. Its use has been deprecated in September 2004 by RFC 3879 and systems must not support this special type of address.

IPv6 packet

The IPv6 packet is composed of two main parts: the header and the payload.

The header is in the first 40 octets (320 bits) of the packet and contains:

• Version - version 6 (4-bit IP version).
• Traffic class - packet priority (8-bits). Priority values are divided into ranges: traffic where the source provides congestion control and non-congestion control traffic.
• Flow label - QoS management (20 bits). Originally created for giving real-time applications special service, but currently unused.
• Payload length - payload length in bytes (16 bits). When cleared to zero, the option is a "Jumbo payload" (hop-by-hop).
• Next header - Specifies the next encapsulated protocol. The values are compatible with those specified for the IPv4 protocol field (8 bits).
• Hop limit - replaces the time to live field of IPv4 (8 bits).
• Source and destination addresses - 128 bits each.

 IPv6 and the Domain Name System

The Domain Name System (DNS) is fundamental to how name resolution works on both IPv4 and IPv6 networks. On an IPv4 network, host (A) records are used by name servers (DNS servers) to resolve fully qualified domain names (FQDNs) like server1.contoso.com into their associated IP addresses in response to name lookups (name queries) from DNS clients. In addition, reverse lookups-in which IP addresses are resolved into FQDNs-are supported by using pointer (PTR) records in the in-addr.arpa domain.

 Name resolution works fundamentally the same way with IPv6, with the following differences:

 •Host records for IPv6 hosts are AAAA ("quad-A") records, not A records.

 •The domain used for reverse lookups of IPv6 addresses is ip6.arpa, not in-addr.arpa.

Transition mechanisms

Until IPv6 completely supplants IPv4, which is not likely to happen in the foreseeable future, a number of so-called transition mechanisms are needed to enable IPv6-only hosts to reach IPv4 services and to allow isolated IPv6 hosts and networks to reach the IPv6 Internet over the IPv4 infrastructure. Contains an overview of the transition mechanisms mentioned below.

Dual stack

One important mechanism is to allow IPv6 hosts and routers to be implemented in such a way that that supports both IPv4 and IPv6 while sharing most of the code. Such an implementation is called a dual stack or dual IP layer. Most current implementations of IPv6 use a dual stack.

Tunneling

In order to reach the IPv6 Internet, an isolated host or network must be able to use the existing IPv4 infrastructure to carry IPv6 packets. This is done using a technique known as Tunneling, It enables incompatible networks to be bridged, and is usually applied in a point-to-point or sequential manner.

Three mechanisms of tunneling are presented:

IPv6 over IPv4,

IPv6 to IPv4 automatic tunneling,

Tunnel Broker.

which consists of encapsulating IPv6 packets within IPv4, in effect using IPv4 as a link layer for IPv6.

IPv6 packets can be directly encapsulated within IPv4 packets using protocol number 41. They can also be encapsulated within UDP packets e.g. in order to cross a router or NAT device that blocks protocol 41 traffic. They can of course also use generic encapsulation schemes, such as AYIYA or GRE.

Automatic tunneling

Automatic tunneling refers to a technique where the tunnel endpoints are automatically determined by the routing infrastructure. The recommended technique for automatic tunneling is 6to4 tunneling, which uses protocol 41 encapsulation. Tunnel endpoints are determined by using a well-known IPv4 anycast address on the remote side, and embedding IPv4 address information within IPv6 addresses on the local side. 6to4 is widely deployed today.

ISATAP

Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) defines ISATAP addresses used between two nodes running both IPv4 and IPv6 over a private intranet. ISATAP addresses use the locally administered interface ID ::0:5EFE:w.x.y.z in which w.x.y.z is any unicast IPv4 address, public or private. You can combine the ISATAP interface ID with any 64-bit prefix that is valid for IPv6 unicast addresses, including the link-local address prefix (FE80::/64), site-local prefixes, and global prefixes.

Teredo address

The Teredo address is used for communicating between two nodes running both IPv4 and IPv6 over the Internet when one or both of the endpoints are located behind an IPv4 network address translation (NAT) device. You form the Teredo address by combining the 2001::/32 Teredo prefix with the public IPv4 address of a Teredo server and other elements. Teredo is an IPv6 transition technology described in RFC 4380

Tunnel Broker

Configured tunneling is a technique where the tunnel endpoints are configured explicitly, either by a human operator or by an automatic service known as a tunnel broker. Configured tunneling is usually more deterministic and easier to debug than automatic tunneling, and is therefore recommended for large, well-administered networks.

Configured tunneling uses protocol 41 in the Protocol field of the IPv4 packet. This method is also better known as 6in4.

Windows Network Commands

The network commands which can be useful when networking with other computers both within the network and across the internet, obtaining more information about other computers. When using command-line tools in Windows Vista it is healthy to remember to launch the command prompt window with administrative privileges. In order to do so, press [windows button + R] enter "cmd"

netstat

Displays active TCP connections, status of ports are i.e. open, closed, waiting, Ethernet statistics, the IP routing table, IPv4 statistics (for the IP, ICMP, TCP, and UDP protocols), and IPv6 statistics (for the IPv6, ICMPv6, TCP over IPv6, and UDP over IPv6 protocols). Used without parameters, netstat displays active TCP connections. It will also display various other things. It has many different options.

-a	Displays all connections and listening ports.
-e	Displays Ethernet statistics. This may be combined with the -s option.
-n	Displays addresses and port numbers in numerical form.
-p	Proto Shows connections for the protocol specified by proto; proto may be TCP or UDP. If used with the -s option to display per-protocol statistics, proto may be TCP, UDP, or IP.
-r	Displays the routing table.
-s	Displays per-protocol statistics. By default, statistics are shown for TCP, UDP and IP; the -p option may be used to specify a subset of the default.
Interval	Redisplays selected statistics, pausing interval seconds between each display. Press CTRL+C to stop redisplaying statistics. If omitted, netstat will print the current configuration information once.

ipconfig

Displays the network settings currently assigned to any or all network adapters in the machine. This command can be utilized to verify a network connection as well as to verify your network settings and the command could be /all, /flushdns, /renew /release etc.

/all	Display full configuration information.
/release	Release the IP address for the specified adapter.
/renew	Renew the IP address for the specified
/flushdns	Purge the DNS Resolver cache.
/registerdns	Refresh all DHCP leases and re-register DNS names.
/displaydns	Display the contents of the DNS Resolver Cache.
/showclassid	Display all the DHCP class IDs allowed for adapter.
/setclassid	Modify the dhcp class id.

tracert

Tracert will show the route of a packet being sent and received. It attempts to list the series of hops through which your packets travel on their way to a given destination.

-d	Do not resolve addresses to hostnames
-h	Maximum number of hops to search for target
-j	Loose source route along host-list <IPV4 only>
-w	Wait timeout milliseconds for each reply.
-R	Trace round – trip path <IPV6 only>
-S	Source address to use <IPV6 only>
-4	Force using IPV4
-6	Force using IPV6

ping

The ping command helps in determining TCP/IP Networks IP address as well as determine issues with the network by sending echo requests to the host you specify on the command line, and lists the responses received their round trip time and assists in resolving them.

-t	Ping the specified host until stopped
-a	Resolve address to hostnames
-n count	Number of echo requests to send
-l size	Send buffer size
-I TTL	Time to live
-f	Set don’t fragment flag in packet <IPV4 only>
-v TOS	Type of service <IPV4 only This setting has been deprecated and has no effect on the type of service field in the IP Header>.
-r count	Record route for count hops <IPV4 only>.
-s count	Timestamp for count hops <IPV4 Only>.
-j host-list	Loose source route along host-list <IPV4-Only>.
-k host-list	Strict source route along host-list <IPV4 only>
-w timeout	Timeout in milliseconds to wait for each reply
-R	Use routing header to test reverse route also <IPV6 only>
-S srcaddr	Source address to use
-4	Force using IPV4
-6	Force using IPV6

pathping

Pathping is the advance (newer version) of tracert Provides information about network latency and network loss at intermediate hops between a source and destination. Pathping sends multiple Echo Request messages to each router between a source and destination over a period of time and then computes results based on the packets returned from each router.

  

-g host-list	Loose source route along host-list.
-h maximum-hops	Maximum number of hops to search for target.
-i address	Use the specified source address.
-n	Do not resolve addresses to hostnames.
-p period	Wait period milliseconds between pings.
-q num_queries	Number of queries per hop.
-w timeout	Wait timeout milliseconds for each reply.
-4	Force using IPV4
-6	Force using IPV6

telnet

Telnet is software that allows users to remotely access another computer such as a server, network device, or other computer. With telnet users can connect to a device or computer, manage a network device, setup a device, transfer files, etc.

 You get this error in windows 7 because unlike XP ,Vista does not support telnet command by default. So, for this you have to manually enable/turn on the telnet feature in windows 7

Here’s the step by step procedure to enable telnet feature (telnet command) in Windows Vista/7.

1. Go to the Control Panel.

2. Click on the sub heading Uninstall a program under the main heading Programs.

NOTE: IF you are in the Classic View click on Programs and Features.

3. Now in the left panel under the Tasks select the option Turn Windows features on or off.

4. Check Telnet Client

Hit OK

  

-a	Attempt automatic logon on user’s name.
-e	Escape character to enter telnet client prompt.
-f	File name for client side logging
-l	Specifies the user name to log in with on the remote system.
-t	Specifies terminal type.
host	Specifies the hostname or IP address of the remote computer
port	Specifies a port number or service name.

route

The function and syntax of the Windows ROUTE command is similar to the UNIX or Linux route command. Use the command to manually configure the routes in the routing table.

-f	Clears the routing table of all gateway entries.
-p	When used with the ADD command, make a route persistent across boots of the system. By default, routes are not preserved when the system is restarted. Ignored for all other commands, which always affect the appropriate persistent routes.
Command	One of these:
PRINT	Prints a route
ADD	Adds a route
DELETE	Deletes a route
destination	Specifies the host.
MASK	Specifies that the next parameter is the ‘netmask’ value.
netmask	Specifies a subnet mask value for this route entry.
gateway	Specifies gateway.
interface	The interface number for the specified route.
METRIC	Specifies the metric, i.e., cost for the destination.

ftp

FTP is short for File Transfer Protocol; this page contains additional information about the FTP command and help using that command in UNIX and MS-DOS (Windows).

Command	Description
!	Preceding a command with the exclamation point will cause the command to execute on the local system instead of the remote system.
?	Request assistance or information about the FTP commands. This command does not require a connection to a remote system.
ascii	Set the file transfer mode to ASCII (Note: this is the default mode for most FTP programs).
bell	Turns bell mode on / off. This command does not require a connection to a remote system.
binary	Set the file transfer mode to binary (Note: the binary mode transfers all eight bits per byte and must be used to transfer non-ASCII files).
bye	Exit the FTP environment (same as quit). This command does not require a connection to a remote system.
cd	Change directory on the remote system.
close	Terminate a session with another system.
debug	Sets debugging on/off. This command does not require a connection to a remote system.
delete	Delete (remove) a file in the current remote directory (same as rm in UNIX).
dir	Lists the contents of the remote directory. The asterisk (*) and the question mark (?) may be used as wild cards. For example:
get	WIP
help	Request a list of all available FTP commands. This command does not require a connection to a remote system.
lcd	Change directory on your local system (same as CD in UNIX).
ls	List the names of the files in the current remote directory.
mget	WIP
mkdir	Make a new directory within the current remote directory.
mput	Copy multiple files from the local system to the remote system. (Note: You will be prompted for a "y/n" response before copying each file).
open	Open a connection with another system.
put	Copy a file from the local system to the remote system.
pwd	Find out the pathname of the current directory on the remote system.
quit	Exit the FTP environment (same as "bye"). This command does not require a connection to a remote system.
rmdir	Remove (delete) a directory in the current remote directory.
trace	Toggles packet tracing. This command does not require a connection to a remote system.

nslookup

 Displays information that you can use to diagnose Domain Name System (DNS) information such as ns, a, mx, txt, etc. The Nslookup command-line tool is available only if you have installed the TCP/IP protocol.

NAME	print info about the host/domain NAME using default server
NAME1 NAME2	as above, but use NAME2 as server
help or ?	print info on common commands
set OPTION	set an option All print options, current server and host [no]debug print debugging information [no]d2 print exhaustive debugging information [no]defname append domain name to each query [no]recurse ask for recursive answer to query [no]search use domain search list [no]vc always use a virtual circuit domain=NAME set default domain name to NAME srchlist=N1[/N2/.../N6] set domain to N1 and search list to N1,N2, etc. root=NAME set root server to NAME retry=X set number of retries to X timeout=X set initial time-out interval to X seconds type=X set query type (ex. A,ANY,CNAME,MX,NS,PTR,SOA,SRV) querytype=X same as type class=X set query class (ex. IN (Internet), ANY) [no]msxfr use MS fast zone transfer ixfrver=X current version to use in IXFR transfer request
server NAME	set default server to NAME, using current default server
lserver NAME	set default server to NAME, using initial server
finger [USER]	finger the optional NAME at the current default host
Root	set current default server to the root
ls [opt] DOMAIN [> FILE]	list addresses in DOMAIN (optional: output to FILE) -a list canonical names and aliases -d list all records -t TYPE list records of the given type (e.g. A,CNAME,MX,NS,PTR etc.)
view FILE	sort an 'ls' output file and view it with pg
Exit	exit the program

arp

Displays, adds, and removes arp information from network devices.

-a	Displays current ARP entries by interrogating the current protocol data. If inet_addr is specified, the IP and Physical addresses for only the specified computer are displayed. If more than one network interface uses ARP, entries for each ARP table are displayed.
-g	Same as –a
inet_addr	Specifies an Internet address.
-N if addr	Displays the ARP entries for the network interface specified by if_addr.
-d	Deletes the host specified by inet_addr.
-s	Adds the host and associates the Internet address inet_addr with the Physical address eth_addr. The Physical address is given as 6 hexadecimal bytes separated by hyphens. The entry is permanent.
eth_addr	Specifies a physical address
if_addr	If present, this specifies the Internet address of the interface whose address translation table should be modified. If not present, the first applicable interface will be used.

getmac

 This tool will enable you to display the MAC addresses for network adapters on a system. The Media Access Control (MAC) address for the network card can be accessed both on the local computer and on a network.

/S system	Specifies the remote system to connect to.
/U [domain\]user	Specifies the user context under which the command should execute.
/P [password]	Specifies the password for the given user context. Prompts for input if omitted.
/FO format	Specifies the format in which the output is to be displayed.
/NH	Specifies that the “Column Header” should not be displayed in the output.
/V	Specifies that verbose output is displayed
/?	Displays this help message.

hostname

Tells the user the host name of the computer they are logged into.

nbtstat

nbtstat utility that displays protocol statistics and current TCP/IP connections using NBT.

-a	(adapter status) Lists the remote machine's name table given its name
-e	(Adapter status) Lists the remote machine's name table given its
-A	Displays addresses and port numbers in numerical form.
-c	(cache) Lists the remote name cache including the IP addresses
-n	(names) Lists local NetBIOS names.
-r	(resolved) Lists names resolved by broadcast and via WINS
-R	(Reload) Purges and reloads the remote cache name table
-S	(Sessions) Lists sessions table with the destination IP addresses.
-s	(sessions) Lists sessions table converting destination IP addresses to host names via the hosts file.
RemoteName	Remote host machine name.
IP address	Dotted decimal representation of the IP address.
interval	Redisplays selected statistics, pausing interval seconds between each display. Press Ctrl+C to stop redisplaying statistics.

net

Net is a general tool with commands covering a broad range of functionality.

NET ACCOUNTS	Adjust account settings. [/FORCELOGOFF:{minutes | NO}] [/MINPWLEN:length] [/MAXPWAGE:{days | UNLIMITED}] [/MINPWAGE:days] [/UNIQUEPW:number] [/DOMAIN]
NET COMPUTER	Add other networked computers with Windows Domain Controller. \\computername {/ADD | /DEL}
NET CONFIG	Displays your current server or workgroup settings. [SERVER | WORKSTATION]
NET CONTINUE	Continues the use of service. [service]
NET FILE	Display opened shared files on the server. [id [/CLOSE]]
NET GROUP	Add, delete, view, and otherwise manage network workgroups. [groupname [/COMMENT:"text"]] [/DOMAIN] groupname {/ADD [/COMMENT:"text"] | /DELETE} [/DOMAIN] groupname username [...] {/ADD | /DELETE} [/DOMAIN]
NET LOCALGROUP	Add, delete, view, and otherwise manage network groups. [groupname [/COMMENT:"text"]] [/DOMAIN] groupname {/ADD [/COMMENT:"text"] | /DELETE} [/DOMAIN] groupname name [...] {/ADD | /DELETE} [/DOMAIN]
NET NAME	Create or delete name used for messaging. [name [/ADD | /DELETE]]
NET PAUSE	Pause the specified network service. [service]
NET PRINT	Manage network print jobs. \\computername\sharename [\\computername] job# [/HOLD | /RELEASE | /DELETE]
NET SEND	Sends messages to other users, computers, or messaging names on the network. The Messenger service must be running to receive messages. You can send a message only to a name that is active on the network. If the message is sent to a username, that user must be logged on and running the Messenger service to receive the message. {name | * | /DOMAIN[:name] | /USERS} message
NET SESSION	Display all sessions connected to the computer and deletes them if specified. [\\computername] [/DELETE]
NET SHARE	Create and manage a local network share. sharename sharename=drive:path [/USERS:number | /UNLIMITED] [/REMARK:"text"] [/CACHE:Manual | Documents| Programs | None ] sharename [/USERS:number | /UNLIMITED] [/REMARK:"text"] [/CACHE:Manual | Documents | Programs | None] {sharename | devicename | drive:path} /DELETE
NET START	Start the specified network service. [service]
NET STATISTICS	Display network statistics of the workstation or server. [WORKSTATION | SERVER]
NET STOP	Stop the specified network service. Service
NET TIME	Display the time and date of another network computer. [\\computername | /DOMAIN[:domainname] | /RTSDOMAIN[:domainname]] [/SET] [\\computername] /QUERYSNTP [\\computername] /SETSNTP[:ntp server list]
NET USE	Connects or disconnects your computer from a shared resource or displays information about your connections. [devicename | *] [\\computername\sharename[\volume] [password | *]] [/USER:[domainname\]username] [/USER:[dotted domain name\]username] [/USER:[username@dotted domain name] [/SMARTCARD] [/SAVECRED] [[/DELETE] | [/PERSISTENT:{YES | NO}]] NET USE {devicename | *} [password | *] /HOME NET USE [/PERSISTENT:{YES | NO}]
NET USER	Displays users on the computer or domain. [username [password | *] [options]] [/DOMAIN] username {password | *} /ADD [options] [/DOMAIN] username [/DELETE] [/DOMAIN]
NET VIEW	Displays a list of computers in a specified workgroup or the shared resources available on a specified computer. [\\computername [/CACHE] | /DOMAIN[:domainname]] NET VIEW /NETWORK:NW [\\computername]

netsh

netsh is a command-line scripting utility that allows you to, either locally or remotely, display, modify or script the network configuration of a computer that is currently running.

The netsh command is used for the unified tracing operation available in Windows 7. You can use the Netsh.exe tool to perform the following tasks:

1. Configure routes.
2. Configure filters.
3. Configure routing protocols.
4. Configure interfaces.
5. Display the configuration of a currently running router on any computer.
6. Configure remote access behavior for Windows-based remote access routers that are running the Routing and Remote Access Server (RRAS) Service.
7. Use the scripting feature to run a collection of commands in batch mode against a specified router.

The syntax for the Netsh.exe tool is:
netsh [-r router name] [-a AliasFile] [-c Context] [Command | -f ScriptFile]
To learn how to use Netsh with its switches and parameters, type the context name followed by a space and a? at the netsh> command prompt. Netsh /?. Or to display a list of subcontext and commands that can be used in the interface context, type Netsh Interface / ?

?	Displays a list of commands.
Add	Adds a configuration entry to a list of entries.
advfirewall	Changes to the `netsh advfirewall' context.
Branchcache	Changes to the `netsh branchcache' context.
Bridge	Changes to the `netsh bridge' context.
Delete	Deletes a configuration entry from a list of entries.
Dhcpclient	Changes to the `netsh dhcpclient' context.
Dnsclient	Changes to the `netsh dnsclient' context.
Dump	Displays a configuration script.
Exec	Runs a script file.
Firewall	Changes to the `netsh firewall' context.
Help	Displays a list of commands.
http	Changes to the `netsh http' context.
Interface	Changes to the `netsh interface' context.
Ipsec	Changes to the `netsh ipsec' context.
Lan	Changes to the `netsh lan' context.
Mbn	Changes to the `netsh mbn' context.
Namespace	Changes to the `netsh namespace' context.
Nap	Changes to the `netsh nap' context.
Netio	Changes to the `netsh netio' context.
P2p	Changes to the `netsh p2p' context.
Ras	Changes to the `netsh ras' context.
Rpc	Changes to the `netsh rpc' context.
Set	Updates configuration settings.
Show	Displays information.
Trace	Changes to the `netsh trace' context.
Wcn	Changes to the `netsh wcn' context.
Wfp	Changes to the `netsh wfp' context.
Winhttp	Changes to the `netsh winhttp' context.
Winsock	Changes to the `netsh winsock' context.
Wlan	Changes to the `netsh wlan' context.