HP LaserJet 3050 User Manual

							TCP/IP
Introduction
This section is intended to provide information to help you gain a basic understanding of TCP/IP.
Similar to a common language that people use to communicate with each other, TCP/IP
(Transmission Control Protocol/Internet Protocol) is a suite of protocols designed to define the way
computers and other devices communicate with each other over a network.
TCP/IP is rapidly becoming the most used set of protocols. The main reas\
on this is happening is the
fact that the Internet is based on TCP/IP. If you have a network that you wish to connect to the
Internet, you must be using TCP/IP to communicate.
Internet Protocol (IP)
When information is sent across the network, the  data is broken down into small packets. Each
packet is sent independently of one another. Each packet  is encoded with IP information, such as the
IP address of the sender and receiver. IP packets can be routed over routers and gateways, devices
that connect a network with other networks.
IP communications is connectionless. When IP packets are sent, there is no guarantee that they
arrive at their destination in the proper sequence. That task can be performed by higher level
protocols and applications thereby allowing IP communications to be efficient.
Each node or device that will communicate directly onto the network requ\
ires an IP address.
Transmission Control Protocol (TCP)
TCP handles breaking the data into packets and  recombining the packets on the receiving end by
providing a connection-oriented, reliable, and guaranteed delivery service to another node on the
network. When data packets are received at their destination, TCP calculates a checksum for each
packet to verify the data is not corrupt. If  the data in the packet has been corrupted during
transmission, TCP discards the packet and requests that the packet be resent.
User Datagram Protocol (UDP)
UDP provides similar services to TCP. However, UDP does not acknowledge data receipt and
supports request/reply transactions with no added reliability or guarantee of delivery. UDP is used
when acknowledgment and reliability are not required, such as during a “discovery broadcast.”
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							IP address
Every host (workstation or node) on an IP network requires a unique IP address for each network
interface. This address is a software address that is used to identify both the network and specific
hosts located on that network. Each IP address can be divided into two separate parts: the network
portion and the host portion. It is possible for a host to query a server for a dynamic IP address each
time the all-in-one boots up (for example, using DHCP and BOOTP).
NOTEWhen assigning IP addresses, always consult  the IP address administrator. Setting
the wrong address can disable other equipment operating on the network or interfere with
communications.
IP address: network portion
Network addresses are managed by an organization in Norfolk, Virginia, recognized as InterNIC.
InterNIC has been contracted by the National Science Foundation to manage the Internet addresses
and domains. Network addresses are distributed to organizations that are in turn responsible for
making sure all attached devices or hosts on  the network are properly numbered. For more
information about the network portion of an IP address, see 
IP address structure and class and
Subnets  in this section.
IP address: host portion
Host addresses numerically identify specific network interfaces on an IP network. Usually a host has
only one network interface; thus, only one IP address. Because no two devices can share the same
number at the same time, administrators typically maintain address tables to assure correct
assignment of addresses in the host network.
IP address structure and class
An IP address is comprised of 32 bits of information and divided into 4 sections containing 1 byte
each section or 4 bytes total:
xxx.xxx.xxx.xxx
For efficiency in routing, networks were broken down into three classes,\
 so routing can begin simply
by identifying the leading byte of information in the  IP address. The three IP addresses that InterNIC
assigns are class A, B, and C. The network class determines what each of the four IP address
sections identify as shown below:
Table 9-7   IP address class format
ClassFirst Address Byte
xxx.Second Address
Byte xxx.Third Address Byte
xxx.Fourth Address Byte
xxx
ANetwork.Host.Host.Host.
BNetwork.Network.Host.Host.
C Network.Network.Network.Host.
As illustrated in Table 9-8 Network class characteristics, each network class differs by the leading bit
identifier, the address range, the number of each  type available, and the maximum number of hosts
each class allows.
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							Table 9-8  Network class characteristics
ClassNetwork Class
CharacteristicsAddress RangeMaximum Number of
Networks in the ClassMaximum Hosts in
the Network
A00.0.0.0 to
127.255.255.255.126.Over 16 Million.
B10.128.0.0.0 to
191.255.255.255.16,382.65,534.
C 110.192.0.0.0 to
223.255.255.255. Over 2 Million. 254.
Configuring IP parameters
TCP/IP configuration parameters (such as IP address, subnet mask, default gateway) can be
configured on the all-in-one in a variety of 
ways. These values can be configured manually (for
example, through Telnet, the embedded Web server, the arp and ping commands, and HP
management software), or they can be automatically downloaded using DHCP or BOOTP each time
the all-in-one is turned on.
When powered on, a new all-in-one that is unable  to retrieve a valid IP address from the network will
automatically assign itself a default IP address. The default IP address will depend on the type of
network to which the all-in-one is connected. On a small private network, a technique called link-local
addressing is used to assign a unique IP address in the range of 169.254.1.0 to 169.254.254.255,
which should be valid. On a large or enterprise  network, a temporary address of 192.0.0.192 will be
assigned until it is properly configured for your network. The IP address configured on your all-in-one
may be determined by inspecting the all-in-one Configuration page.
Dynamic Host Configuration Protocol (DHCP)
DHCP allows a group of devices to use a set of IP addresses that are maintained by a DHCP server.
The device or host sends a request to the server,  and if an IP address is available, the server
assigns it to that device.
BOOTP
BOOTP is a bootstrap protocol used to download configuration parameters and host information from
a network server. BOOTP uses UDP for its transport. In order for devices to boot and load
configuration information into RAM, they must communicate through the bootstrap protocol BOOTP
as a client with their server.
To configure the all-in-one, the client broadcasts  a boot request packet containing at least the
hardware address of the all in one (all-in-one hardware address). The \
server answers with a boot
reply packet containing the information the all-in-one needs to configure.
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							Subnets
When an IP network address for a particular network class is assigned to an organization, no
provision is made for more than one network being present at that location. Local network
administrators use subnets to partition a network into several different subnetworks. Splitting a
network into subnets can result in better performance and improved use of limited network address
space.
Subnet mask
The subnet mask is a mechanism used to divide a single IP network into several different
subnetworks. For a given network class, a portion of an IP address that would normally be used to
identify a node is used, instead, to identify a subnetwork. A subnet mask is applied to each IP
address to specify the portion used for subnetworks, and  the portion used to identify the node. For
example, see 
Table 9-9 Example: Subnet mask 255.255.0.0 applied to class A network .
Table 9-9   Example: Subnet mask 255.255.0.0 applied to class A network
Class A Network AddressNetwork 15xxxxxxxxx
Subnet Mask25525500
IP Address fields with Subnet
Mask appliedNetworkSubnetHostHost
Example of a node’s IP Address
on Subnet 1151257
Example of a node’s IP Address
on Subnet 254 15 254 64 2
As illustrated in Table 9-9 Example: Subnet mask 255.255.0.0 applied to class A network
, the Class
A IP network address “15” has been assigned to company ABC. To allow additional networks at
company ABC’s site, the subnet mask of 255.255.0.0  is used. This subnet mask specifies that the
second byte of the IP address will be used to  identify up to 254 subnets. Using this designation, each
device is uniquely identified on its own subnet, but company ABC can incorporate up to 254
subnetworks without violating their assigned address space.
Gateways
Gateways (routers) are used to connect networks together. Gateways are devices that act as
translators between systems that do not use the same communication protocols, data formatting,
structures, languages, or architectures. Gateways repackage the data packets and change the
syntax to match that of the destination system. When networks are divided into subnets, gateways
are required to connect one subnet to another.
Default gateway
The default gateway is the gateway or router that, if not specified, will be used to move packets
between networks. It is specified by an IP address.
If multiple gateways or routers exist,  then the default gateway is typically the address of the first, or
nearest, gateway or router. If no gateways or routers exist, then the default gateway will typically
assume the IP address of the network  node (such as the workstation or all-in-one).
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							10 Convenience stapler (HP LaserJet3392 all-in-one only)
●Understanding the convenience stapler
●
Loading staples
●
Using the convenience stapler
●
Clearing stapler jams
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							Understanding the convenience stapler
A convenience stapler is mounted to the front, right side of the HP LaserJet 3392 all-in-one. Insert up
to 20 sheets of media (80 g/m2 or 20 lb) into the stapler slot to trigger the stapling mechanism and
force a single staple through the media.
NOTE The convenience stapler operates independently from the control panel and all-in-one
software and does not automatically staple print jobs. The stapler requires no settings and
generates no error messages or status messages.
Figure 10-1   Location of convenience stapler
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							Loading staples
Each staple cassette holds 1,500 unformed staples. To load staples into the all-in-one, insert a st\
aple
cassette.
To load staples
1.Open the stapler door.
NOTE Opening the stapler door disables the stapler.
2.If you are replacing a staple cassette (for example, if your staple cassette has run out of
staples), remove the staple cassette from the all-in-one.
3.Insert one 1,500-staple cassette into the opening inside the staple door.
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							4.Close the stapler door.
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							Using the convenience stapler
Activate the stapling mechanism by inserting media into the convenience stapler.
To staple media by using the convenience stapler
1.Insert up to 20 sheets of media (80 g/m
2 or 20 lb) into the slot in the stapler door. Insert fewer
sheets to staple if the media weight is heavier than 80 g/m2 or 20 lb.
CAUTION Do not use the convenience stapler to staple plastic, cardboard, or wood.
Damage to the convenience stapler can result from attempting to staple these materials.
NOTE Exceeding the recommended capacity could result in jams or damage.
2.Wait for the stapler to staple the sheets. When it is inserted all the way into the stapler slot, the
media should trigger the stapler mechanism.
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							3.Remove the stapled media from the slot.
NOTE If you are unable to remove the media after stapling, carefully open the stapler
door and then slide your document out.
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