Windows Name Server - Netbios

Windows Name Server

NetBIOS

The NetBIOS name is 16 ASCII characters, however Microsoft limits the host name to 15 characters and reserves the 16th character as a NetBIOS Suffix. This suffix describes the service or name record type such as host record, master browser record, domain controller record. The host name (or short host name) is specified when Windows networking is installed/configured, the suffixes registered are determined by the individual services supplied by the host. In order to connect to a computer running TCP/IP via its NetBIOS name, the name must be resolved to a network address. Today this is usually an IP address (the NetBIOS name-IP address resolution is often done by either broadcasts or a WINS Server — NetBIOS Name Server). A computer's NetBIOS name is often the same as that computer's host name (see below), although truncated to 15 characters, but it may also be completely different. NetBIOS names can include almost any combination of alphanumeric characters except for spaces and the following characters .

Node types

The node type of a networked computer relates to the way it resolves NetBIOS names to IP addresses. There are four node types.

• B-node: 0x01 Broadcast
• P-node: 0x02 Peer (WINS only)
• M-node: 0x04 Mixed (broadcast, then WINS)
• H-node: 0x08 Hybrid (WINS, then broadcast)

NetBIOS Suffixes

The NetBIOS suffix, alternately called the NetBIOS End Character (endchar) is the 16th character of a NetBIOS name. This character specifies the record or service type for the registered name record. The number of record types is limited to 255, the number that will fit into a single character. However in actual use the number of commonly used NetBIOS Suffixes is substantially smaller. The most common NetBIOS Suffixes:

ASCII Values of 16th characters of NetBIOS "names"

• 00: Workstation Service
• 03: Messenger Service
• 20: File Service (also called Host Record)
• 1B: Domain Master Browser - Primary Domain Controller for a domain
• 1C: Domain Controllers for a domain (group record with up to 25 IP addresses)
• 1D: Master Browser
• 1E: Browser Service Elections

Services

NetBIOS provides three distinct services:

• Name service for name registration and resolution.
• Session service for connection-oriented communication.
• Datagram distribution service for connectionless communication.

(Note: SMB, an upper layer, is a service that runs on top of the Session Service and the Datagram service, and is not to be confused as a necessary and integral part of NetBIOS itself. It can now run atop TCP with a small adaptation layer that adds a packet length to each SMB message; this is necessary because TCP only provides a byte-stream service with no notion of packet boundaries.)

Name service (UDP 137)

In order to start Sessions or distribute Datagrams, an application must register its NetBIOS name using the Name service. NetBIOS names are 16 bytes in length and vary based on the particular implementation. Frequently, the 16th byte is used to designate a "type" similar to the use of ports in TCP/IP. In NBT, the name service operates on UDP port 137 (TCP port 137 can also be used, but it is rarely if ever used).

The name service primitives offered by NetBIOS are:

• Add Name — registers a NetBIOS name.
• Add Group Name — registers a NetBIOS "group" name.
• Delete Name — un-registers a NetBIOS name or group name.
• Find Name — looks up a NetBIOS name on the network.

Session service (TCP 137)

Session mode lets two computers establish a connection for a "conversation", allows larger messages to be handled, and provides error detection and recovery. In NBT, the session service runs on TCP port 139.

The session service primitives offered by NetBIOS are:

• Call — opens a session to a remote NetBIOS name.
• Listen — listen for attempts to open a session to a NetBIOS name.
• Hang Up — close a session.
• Send — sends a packet to the computer on the other end of a session.
• Send No Ack — like Send, but doesn't require an acknowledgment.
• Receive — wait for a packet to arrive from a Send on the other end of a session.

In the original protocol used to implement NetBIOS services on PC-Network, to establish a session, the computer establishing the session sends an Open request which is responded to by an Open acknowledgment. The computer that started the session will then send a Session Request packet which will prompt either a Session Accept or Session Reject packet. Data is transmitted during an established session by data packets which are responded to with either acknowledgment packets (ACK) or negative acknowledgment packets (NACK). Since NetBIOS is handling the error recovery, NACK packets will prompt retransmission of the data packet. Sessions are closed by the non-initiating computer by sending a close request. The computer that started the session will reply with a close response which prompts the final session closed packet.

Datagram distribution service (UDP 138)

Datagram mode is "connectionless". Since each message is sent independently, they must be smaller; the application becomes responsible for error detection and recovery. In NBT, the datagram service runs on UDP port 138.

The datagram service primitives offered by NetBIOS are:

• Send Datagram — send a datagram to a remote NetBIOS name.
• Send Broadcast Datagram — send a datagram to all NetBIOS names on the network.
• Receive Datagram — wait for a packet to arrive from a Send Datagram operation.
• Receive Broadcast Datagram — wait for a packet to arrive from a Send Broadcast Datagram operation.

Following commands are used in netbios:

# netstat -> to check the status of netbios

#nbtstat -> to check protocol statistics and current TCP/IP connections using netbios

#nbtstat – a -> to check the netbios name of remote system

#arp -> address resolution protocol

Finding the MAC Address of Remote Computer

Every device on a TCP/IP network has a unique number assigned to it called the MAC (Media Access Control) address. The MAC address is used by the network hardware such as routers, switches, etc. to send traffic from one device to another device on your network.

Your computer uses a service called ARP (Address Resolution Protocol) to resolve and track the TCP/IP and MAC address of the remote devices that you're communicating with. This information is handy for doing semi-low level network troubleshooting. It can also be used for granting or denying permissions to a network segment or device on that network.

To determine the MAC address of a remote device:

• Open the MS-DOS prompt (From the Run... command, type "CMD" and press Enter).
• Ping a remote device that you want to find the MAC address (for example: PING 192.168.0.1).
• Type "ARP -A", and press Enter.

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\WINDOWS>arp -a

Interface: 192.168.1.100 --- 0x10004
Internet Address Physical Address Type
192.168.1.1 aa-fb-c8-34-da-7a dynamic

Creating Domain controller in windows 2003

Preface:

One of the greatest features of Windows Server 2003 is its ability to be a Domain Controller (DC). The features of a domain extend further than this tutorial ever could, but some of its most well known features are its ability to store user names and passwords on a central computer (the Domain Controller) or computers (several Domain Controllers). In this tutorial we will cover the "promoting" (or creating) of the first DC in a domain. This will include DNS installation, because without DNS the client computers wouldn't know who the DC is. You can host DNS on a different server, but we'll only deal with the basics.

Method:

Click Start -> Run...

Type "dcpromo" and click "OK"

You will see the first window of the wizard. As it suggests, I suggest reading the help associated with Active Directory. After this, click "Next"

Click "Next" on the compatibility window, and in the next window keep the default option of "Domain Controller for a new domain" selected, and click "Next"

In this tutorial we will create a domain in a new forest, because it is the first DC, so keep that option selected

Now we have to think of a name for our domain. If you own a web domain like "visualwin.com", you can use it, but it isn't suggested because computers inside of your domain may not be able to reach the company website. Active Directory domains don't need to be "real" domains like the one above - they can be anything you wish. So here I will create "visualwin.testdomain"

Now in order to keep things simple, we will use the first part of our domain ("visualwin"), which is the default selection, as the NetBIOS name of the domain

The next dialog suggests storing the AD database and log on separate hard disks, and so do I, but for this tutorial I'll just keep the defaults

The SYSVOL folder is a public share, where things like .MSI software packages can be kept when you will distribute packages (as I said, AD has a lot of different features). Once again, I will keep the default selection but it can be changed if you wish to use the space of another drive

Now we will get a message that basically says that you will need a DNS server in order for everything to work the way we want it (i.e., our "visualwin.testdomain" to be reachable). As I mentioned earlier, we will install the DNS server on this machine as well, but it can be installed elsewhere. So keep the default selection of "Install and configure", and click "Next"

Because, after all, this is a Windows Server 2003 tutorial website, we'll assume there are no pre-Windows 2000 servers that will be accessing this domain, so keep the default of "Permissions compatible only with Windows 2000 or Windows Server 2003 operating systems" and click "Next"

The restore mode password is the single password that all administrators hope to never use, however they should also never forget it because this is the single password that might save a failed server. Make sure it's easy to remember but difficult to guess

Now we will see a summary of what will happen. Make sure it's all correct because changing it afterwards can prove to be difficult

After the previous next was clicked, the actual process occurs. This can take several minutes. It's likely that you will be prompted for your Windows Server 2003 CD (for DNS) so have it handy

If your computer has a dynamically assigned address (from DHCP) you will be prompted to give it a static IP address. Click ok, and then in the Local Area Connection properties, click "Internet Protocol (TCP/IP)" and then "Properties"

In the next window select "Use the following IP address" and select the information that you will use for your domain (and 127.0.0.1 for the primary DNS, because your computer will host DNS. I still suggest setting up an alternate as well.) Click "OK" and then "Close" on the next window

And after a while you will see

And we're finished.

About me

Hi

This is Balaji. About me????? if i know about me , i will be great human being.But unfortunately still it doesnt happened.
ok.lets come to the matter, I am working as system administrator in one of Information technology company.Everyone think i want to become software engineer,mechnaical engineer and etc.,.But in system administration field most probably it wont happen.The same case happend in my life.but once you came to know about the system administration domain after then you will enjoy even you can be stick with this domain.now am enjoying this domain.
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Lets meet with Real Challenges and Chanllegers....................