There are two different types of names along these page:

• device names: a device has a unique readable name assigned to it.
• NetBIOS names: some applications in a computer  use these names to communicate with some device o some service place at another computer through the NetBIOS protocol.

NetBIOS Name Resolution
Application Layer names (NetBIOS and Sockets host names) must ultimately resolve to Data Link Layer (MAC) addresses.
NBF uses NetBIOS names natively, then resolves them to MAC addresses.
In TCP/IP, NetBT resolves NetBIOS names to IP addresses, which then resolve to MAC addresses via ARP cache or broadcast.
In NWLink, NBIPX resolves NetBIOS names to IPX addresses. IPX addresses contain the MAC address as the host ID, so IPX requires no further resolution.

Sockets Host Name Resolution
For Windows Sockets applications, TCP/IP resolves host names to IP addresses, which then resolve to MAC addresses.

Referencias

    NAT es una herramienta de enlace entre una red IP local e Internet.

    The NAT contains a pool of available global addresses which are constantly reused . Internal Network addresses are allocated according to internal considerations of the Network. Global addresses must remain unique in order to distinguish between different hosts. When a packet is routed, the NAT replaces the internal corporate address with a temporary global address. As soon as the application session is over, the global address is returned to the pool to be reassigned.
 

Muestra estadísticas del protocolo y conexiones TCP/IP actuales utilizando NBT (NetBIOS sobre TCP/IP).

NBTSTAT [-a Nombre remoto] [-A dirección IP] [-c] [-n] [-r] [-R] [-s] [-S] [intervalo] ]
 

    A programmer communicates with the NetBIOS API using Network Control Blocks (NCB).

Microsoft networking protocols communicate with network card drivers using  the Network Driver Interface Specification.
The NDIS interface supports basic services that allow a protocol module to send raw packets over a network device, and allow it to be notified of incoming packets received by a network device. NDIS-compliant drivers are available for a wide variety of network interface cards from many vendors

The standard defines two entities:

• A Session Layer interface that is a standard API for user applications to submit network I/O and control directives to underlying network protocol software. NetBIOS commands are submitted via Network Control Blocks (NCBs).
• A session management/data transport protocol called NetBIOS Frames Protocol (NBFP). NBFP functions at the Session and Transport Layers to perform the network I/O to accommodate the NetBIOS interface command set.

A NetBIOS session is a logical connection between any two names on the network. A session is established by having an NCB.LISTEN issued from one name and an NCB.CALL issued from the other name. Once a session is established, two-way, guaranteed-delivery communication is possible between the two names.

Two basic types of data transfer are supported. Reliable data transfer is provided by the session layer. If data is lost or errors occur, NetBIOS returns an error code to the application program through the NCB. Data transfer using datagram support goes directly to the link layer. This type of data transfer is "best effort" and receipt of data is not guaranteed.

Nombres NetBIOS

    The NetBIOS namespace is flat, meaning that all names within a network must be unique. NetBIOS names are 16 characters in length. Resources are identified by NetBIOS names, that are registered dynamically when computers boot, services start, or users log on. Names can be registered as unique (one owner) or as group (multiple owner) names. A NetBIOS Name Query is used to locate a resource by resolving the name to an IP address. Microsoft networking components, such as Windows NT Workstation and Windows NT Server services, allow the first 15 characters of a NetBIOS name to be specified by the user or administrator, but reserve the 16th character of the NetBIOS name to indicate a resource type (00-FF hex).

    Names are used as the basis for communication between application programs. If the name is in the NetBIOS name table, a session can be established. NetBIOS can have from 1 to 254 selectable names and one NAME_NUMBER_1. The NAME_NUMBER_1 is always present and consists of 10 bytes of binary zeros followed by the adapter's universally administered address. This NetBIOS name is referred to as NetBIOS_NAME_NUMBER_1.
 

Sufijos NetBIOS
The NetBIOS naming convention allows for 16 characters in a NetBIOS name. Microsoft, however, limits NetBIOS names to 15 characters and uses the 16th character as a NetBIOS suffix to identify functionality installed on the registered device.

The following table lists the NetBIOS suffixes that are used by Microsoft Windows NT. The suffixes are listed in hexadecimal format because many of them are unprintable otherwise.
 
 
 

 NetBIOS name types describe the functionality of the registration.

• Unique (U): The name may have only one IP address assigned to it. On a network device multiple occurrences of a single name may appear to be registered. The suffix may be the only unique character in the name.
• Group (G): A normal group; the single name may exist with many IP addresses. WINS responds to a name query on a group name with the limited broadcast address (255.255.255.255). Because routers block the transmission of these addresses, the Internet Group was designed to service communications between subnets.
• Multihomed (M): The name is unique, but due to multiple network interfaces on the same computer this configuration is necessary to permit the registration. The maximum number of addresses is 25.
• Internet Group (I): This is a special configuration of the group name used to manage Windows NT Domain names.
• Domain Name (D): New in Windows NT 4.0.

Referencias

    The Windows NT implementation of NetBIOS over TCP/IP is referred to as "NetBT". NetBT uses the following TCP and UDP ports:

• UDP port 137 (name services)
• UDP port 138 (datagram services)
• TCP port 139 (session services)

    NetBIOS over TCP/IP is the network component that performs name resolution (NETBT.SYS in Windows NT and VNBT.VXD in Windows for Worgroups and Windows 95).

NetBIOS Name Registration and Resolution

    Windows NT systems may use several methods for locating NetBIOS resources:

• NetBIOS name cache
• NetBIOS name server
• IP subnet broadcasts
• Static LMHOSTS files
• Static HOSTS files
• DNS servers
• WINS servers

B-Node                     Broadcasts are used for both name registration and name resolution.

On a TCP/IP network, if the IP router is not configured to forward the name registration and name query broadcasts, systems on different subnets will not be able to see each other since they will not receive the broadcasts. B-node name resolution is not the best option on larger networks because its reliance on broadcasts can load the network with broadcasts.

Microsoft Modified B-Node:
The TCP/IP used in Microsoft Windows NT uses a modified version of b-node name resolution. Microsoft modified b-node name resolution works in the following manner:

• The workstation first checks the LMHOSTS cache and, if it finds the NetBIOS name, returns the IP address.
• Next, the workstation tries broadcasting to resolve the name (this works in the same manner as b-node resolution) and, if the destination system is active, it returns its IP address.
• Finally, the workstation (if it is a Windows NT system) will check the LMHOSTS file in the \<winnt_root>\system32\drivers\etc directory

Microsoft-enhanced – Local LMHOSTS files or WINS proxies plus Windows Sockets gethostbyname() calls (using standard DNS and/or local HOSTS files) in addition to standard node types.

P-Node (or Point to Point Node)            Uses a NetBIOS Name Server for name registration and resolution

When using p-node name resolution, broadcasts are NOT used for name registration or name resolution. Instead, all systems register themselves with a NetBIOS Name Server (NBNS) upon start up. The NBNS is responsible for mapping computer names to IP addresses and making sure that no duplicate names are registered on the network. All systems must know the IP address of the NBNS, which is equivalent to a WINS Server. If the systems are not configured with the correct IP address for the NBNS, p-node name resolution will not work.

The p-node name resolution method uses directed User Datagram Protocol (UDP) datagrams and TCP sessions for its communication to and from the NBNS.

The main drawback of p-node name resolution is that if the NBNS cannot be accessed, there will be no way to resolve names and thus no way to access other systems on the network.

 M-Node (or Mixed Node)        Name registration: broadcasts. Name resolution: broadcasts first, but uses p-node if no answer is received

M-node uses a combination of b-node and p-node for name resolution. This method first uses b-node and then p-node, which in theory should increase local area network (LAN) performance. M-Node has the advantage over p-node in that if the NBNS is unavailable, systems on the local subnet can still be accessed through b-node resolution.

M-node is typically not the best choice for larger networks because it uses b-node and thus results in broadcasts. However, when you have a large network that consists of smaller subnetworks connected via slow Wide Area Network (WAN) links, M-node is a preferred method since it will reduce the amount of communication across the slow links.
 

H-Node (or Hybrid node)             Uses p-node. If there is no name server changes to b-node until the server is back

H-node name resolution, which is currently in RFC draft form, also uses both b-node and p-node, however it only uses b-node as a last resort. When configured to use h-node, a system will always first try to use p-node and then use b-node ONLY if p-node fails. In addition, a system can be configured to use the LMHOSTS file after p-node fails and before trying b-node.H-node resolution does not require successful p-node registration for a system to initialize, however the system will use strictly b-node until p-node registration succeeds. If the NBNS is unavailable and the system resorts to using b-node resolution, it will continue to attempt to contact the NBNS so that it can return to using p-node if the NBNS becomes available.

    NetBIOS sessions are established between two names. For instance, when a Windows NT Workstation makes a file sharing connection to a server, the following sequence of events takes place:

• The NetBIOS name for the server is resolved to an IP address.
• A TCP connection is established from the workstation to the server, using port 139.
• The workstation sends a NetBIOS Session Request to the server name over the TCP connection. Assuming the server is listening on that name, it will respond affirmatively and a session is established.

NetBIOS Datagram Services

    Datagrams are sent from one NetBIOS name to another over UDP port 138. The datagram service provides the ability to send a message to a unique name or to a group name. Group names may resolve to a list of IP addresses, or a broadcast. For instance, the command net send /d:mydomain test would send a datagram containing the text "test" to the group name <mydomain>[03]. The <mydomain>[03] name would resolve to an IP subnet broadcast, so the datagram would be sent with the following characteristics:

• Destination MAC address: broadcast (FFFFFFFFFFFF).
• Source MAC address: The NIC address of the local computer.
• Destination IP address: The local subnet broadcast address.
• Source IP address: The IP address of the local computer.
• Destination name: <mydomain>[03] (the messenger service on the remote computers).
• Source name: <localmachine>[03] (the messenger service on the local computer).

The NWLink IPX/SPX-compatible transport in Windows NT uses two distinctly different types of network numbers:

• Windows NT uses an IPX network number for routing purposes. 
  This number is assigned to each configured frame type and adapter combination on your computer. 
  This number is sometimes referred to as the "external network number," and it must be unique for each network segment.
• Windows NT also uses an internal network number for internal routing purposes. 
  The internal network number is also known as a "virtual network number." 
  The internal network number uniquely identifies the computer on the inter-network.

Network Number
You must assign an IPX network number for each frame type configured on each adapter in your computer running Windows NT. This network number must be unique for each network segment. Thus, all computers on the same segment using a given frame type must use the same network number to communicate with each other. If you do not set such a value for the IPX network number in the registry, the NetworkNumber parameter displays a value of "0", but the number itself will be assigned by Windows NT through autodiscovery.

The NetworkNumber key (NetworkNumber: REG_MULTI_SZ) specifies the network number to be used for this adapter. If it is 0, NWLink gets the network number from the network as it is running. A nonzero value will force the use of that number as the external network number for the specific frame type. IPX network numbers are 4 bytes (8 hex characters) long. It is possible to be running multiple IPX networks over the same physical network segment provided they are different frame types.

The frame type is set by registry key (PktType: REG_DWORD). NWLink supports Ethernet, Token Ring, FDDI, and Arcnet topologies. The PktType parameter specifies the packet form to use. The valid values are:

• 0 (Ethernet II)
• 1 (Ethernet 802.3)
• 2 (802.2)
• 3 (SNAP)
• 4 (Arcnet)

Internal Network Number
The internal network number identifies a virtual network segment inside of your computer. That is, the internal network number identifies another (virtual) segment on the internetwork. So, if you configure an internal network number for a computer running Windows NT, a NetWare server or a router will add an extra hop in its route to that computer.

The function of the internal network number parallels the function of the internal IPX network number on a NetWare server. The internal IPX network number on a NetWare file server assigns a "logical" network for the server that helps to uniquely identify the server in a multiple network environment.

Windows NT does not autodetect the internal network number. In certain cases, you may need to manually set a unique nonzero, internal network number. You may need to do this for one or more of the following reasons:

• You choose to use multiple frame types on a single adapter.
• You have bound NWLink to multiple adapters on your computer running Windows NT.
• Your computer is acting as a server running Windows NT for an application that uses the NetWare Service Advertising Protocol (SAP), such as SQL Server or Systems Network Architecture (SNA) Server.

    'In the current configuration the Internal Network Number cannot be 0. A random Internal Network Number has been chosen for you. Please make sure this does not conflict with any other Network Number or select another unique number.'

So, in most cases, the Windows NT internal network number is not present as a packet on the LAN segment. The default value of zero (0) for the internal network number does not show up when you run the IPXROUTE CONFIG command at a command prompt. However, if you have configured such an internal network number, or FPNW has assigned one to your computer, then you may see this internal network number in a trace of a RIP or a SAP broadcast from your computer. The internal network number is not automatically announced to the inter-network.

The internal network number is an eight-digit hexadecimal number with allowed values in the range of 1 to FFFFFFFE, and this number has to be unique across the inter-network. The parameter used to set this number is the VirtualNetworkNumber parameter.

Notice that, although the internal network number is associated with internal routing on your computer running Windows NT, the internal network number does not facilitate IPX routing between separate segments configured on a single Windows NT workstation or server. Windows NT does not natively act as an IPX router. For that added functionality, you will need to install the Microsoft Multi-Protocol Router (MPR) product.

Windows NT version 4.0
In Windows NT version 4.0, you can change both the (external) network number and internal network number through the graphic user interface (GUI) in Control Panel -> Network -> Protocols -> NWLink IPX/SPX Compatible Transport.

Referencias

You can use the program nslookup from the NT Command Prompt to query a DNS server and verify that it is functioning properly.

Invoke nslookup by entering the command "nslookup" and note any error messages. The nslookup program should identify the name and IP address of the default server it is using, which should be the DNS server you are using, and then it should display a command prompt ">". If you are testing the server from another system, or if the current system is pointing to another DNS server as it’s primary, use the nslookup command "server" to change servers (e.g. to set the server to DNS.FeBI.COM use the command: server dns.febi.com or server 111.111.111.111).

If you want to look for a name, enter it at the nslookup command prompt. This will query the selected server for the IP address of the system named name. On a system configured as shown in the above example the result of this would be:

   > name
   Server:  dns.febi.com
   Address:  111.111.111.111

   Name:   name
   Address:   222.222.222.222
   Aliases:   www.name.com

   >

To check your Reverse Arpa, enter the nslookup command "set q=any" to display all information that is given as a result of a query. Then enter the nslookup command "198.146.217.205.IN-ADDR.ARPA". On a system with the example configuration files, the result of this would be:
 

   > set q=any
   > 198.146.217.205.IN-ADDR.ARPA
   Server:  dns.wlw.com
   Address:  205.217.146.198

   198.146.217.205.IN-ADDR.ARPA  name = dns.wlw.com
   146.217.205.IN-ADDR.ARPA  nameserver = dns.wlw.com
   146.217.205.IN-ADDR.ARPA  nameserver = ns1.berkeley.edu
   ns1.berkeley.edu  internet address = 128.32.136.9
   >

This tells you that the reverse arpa setup is functioning properly and is resolving PTR lookups.

To exit from the nslookup program use the command "exit".