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We know from the four pairs of twisted-pair cable in accordance with strict rules and closely twisted together, used to reduce crosstalk and background noise. Meanwhile, in the T568A and T568B standards standards using only the four twisted pair lines 1,2 and 3,6, which is used to send 1,2, 3,6 for receiving, and must come from a 1,2 around the right, around 3,6 must come from a pair. The only way to avoid crosstalk as possible to ensure the data transfer. Read it all..

First look at your wireless router’s default IP address, then open IE or My Computer in the address bar enter the router’s IP, enter the login screen, the default administrator user name admin, password blank. Use “Setup Wizard” to quickly and easily set up the router, click on “online setup wizard” Start Setup Wizard. Read it all..

Show version – software version, config files, boot images, config register, basic config of router
Show ipx interface – status, ipx rip and sap received/sent, ipx access-lists
Show ipx route – ipx routing table
Show ipx servers – server list (name, port, hops, type of service)
Show ipx traffic – number/type of packets, RIP and SAP packets
Show protocol – ipx addresses of an interface, IP addresses and routing protocol
Show ip protocol – routing update times, networks active on, neighbour routers, administrative distances, AS number
Show access-lists – shows standard and extended access-lists on all interfaces
Show access-list 101
Show ip interface – IP addresses, masks, MTU, access-lists, split horizon, ICMP, CDP status, NAT statistics, LMI info, DLCIs
Show interface serial 0 – shows bandwidth, MTU, keepalives
Show ip route – ip routing table
Show cdp neighbor – deviceID, local intf, holdtime, capability, platform, remote portID
Show cdp entry * – IP address of neighbour, protocol info, platform, capability, portID, holdtime, same info as show version, neighbour device ID, local interface
Show cdp neighbor detail – same as above also IP address, version info
Show cdp traffic – info on traffic and errors
Show cdp interface – encapsulation, timer, holdtime for each intf
Show controllers serial 0 – shows DTE/DCE connections, buffer size, collisions, mac address
Show host(s) – shows hostname to IP resolution of hosts
Show session(s) – shows connections to a remote device
Show users – shows connections to your router, port and time connected
Show frame-relay lmi – lmi errors and lmi type
Show frame-relay pvc – all configured PVC’s, DLCI numbers, status of connections, No. of BECN/FECN
Show frame-relay pvc 16
Show frame-relay map – ip to dlci mappings
Show run – display router config (RAM), configured PVCs, ACLs.

GENERAL ROUTER COMMANDS

Banner exec – for activation or incoming vty
Banner incoming – displayed on reverse telnet sessions
Banner login – displayed on all connected terminals. Displayed before MOTD banner but before login prompts
Bfe – manual emergency mode setting
Clear counters – clears counters on all interfaces
Clear frame-relay-inarp – clears dynamic mappings
Clear line 1 – clears vty 1 connection to a remote router
Clock set 10.30.10 28 may 2002
Config-register 0×2102 – changes config register
Copy flash tftp
Copy tftp flash – copies IOS image from tftp server default directory to router flash
Disable – to get back to user mode from privileged
Disconnect 1 – clears a connection to a remote router
Enable – to get into privileged mode
Enable last-resort – define enable action if no tacas servers respond
Enable use-tacas – tells the router to authenticate passwords through a tacas server
Encapsulation isl 3 – encapsulates ISL frame-tagging for VLAN 3 on an interface
Exec timeout 0 1 – sets console timeout to 1 second
Exec-timeout 0 0 – sets exec timeout to never timeout
Exec-timeout 1 0 – set exec timeout to 1 minute
Ip domain-lookup – enables DNS (use no form to stop this)
Ip domain-name nikmakris.com – appends domain name to hostname (required for DNS)
Ip host nik 172.17.1.63 – adds to host table (up to 8 ip addr)
Ip name-server – sets ip address(es) of DNS servers
Lock – locks the terminal
Logging synchronous – stops console messages overwriting commands
Logout – to logout of the router
Media-type 100BaseX – sets media type
Mrinfo – request neigbour and version information from a multicast router
No login – sets line, vty ports not to prompt for login info
Passive-inteface s0 – disables routing updates on interface (Global command) – they are not sent out this interface but they are still received.
Ping ipx 40.0000.0c8d.5c9d
Service password-encryption – encrypts passwords (Global command)
Terminal monitor – needed to view debug commands from telnet session
Terminal history size 50 – sets command history to 50 lines
Tftp-server system <image name> – Make router a tftp server

CONFIGURE COMMANDS

Interface Ethernet 2/0/1 – type slot / port adapter / port number (interface) for VIP cards
Config terminal – configures RAM
Config network (config net) – changes a config on a tftp host
Config memory – configure NVRAM
Ip address 172.17.1.63 255.255.255.0 secondary – adds a secondary subnet address to an interface
Clock rate 56000 – sets clock rate to 56kbps for DCE interfaces

ACCESS LISTS (ACL)

Access-enable – creates a temporary access-list entry
Access-template – creates a temporary access-list entry
Access-profile – apply user profile to interface

Access-list 1 permit 0.0.0.0 255.255.255.255 – same as next line
Access-list 1 permit any – permits any host
Access-list 1 permit 172.30.16.29 0.0.0.0 – same as next line
Access-list 1 permit host 172.30.16.29 – permits host 172.30.16.29
No access list 1 – deletes access list 1
Ip access-group 1 out (out is default)
Access-list 101 deny tcp 172.16.4.0 0.0.0.255 any eq telnet
Access-list 101 permit ip any any established (TCP connection)
Router(Config)#ip access-list standard nik
Router(Config std-nacl)#deny any log (log – logs packets)

No ip access-group in – won’t delete inbound lists if you leave the in off the end of the command

FRAME RELAY

Router(Config)#int s0
Router(Config-if)#encapsulation frame-relay cisco (default)
Router(Config-if)#exit
Router(Config)#int s0.16 point-to-point
Router(Config-if)#no inverse-arp
Router(Config-if)#ip address 172.17.1.63 255.255.255.0
Router(Config-if)#bandwidth 64 – sets bandwidth to 64kbps (Only used by routing protocols)
Router(Config-if)#frame-relay map ip 172.16.30.17 16 ietf broadcast – broadcast tells the router to send broadcasts out this intf

IGRP CONFIGURATION

Router(Config)#router igrp 50
Router(Config-router)#timers basic 15 45 0 60
Router(Config-router)#variance 1-128 (controls load balancing between best and worse metrics)
Router(Config-router)#traffic-share balanced/min
Balanced – share inversely proportional to metrics
Min – use routers that have only min costs
Router(Config-router)#network 128.6.0.0
Router(Config-router)#no metric holddown
Router(Config-router)#metric maximum-hop 50

IPX RIP CONFIGURATION

Router(Config)#ipx routing – enables IPX routing, RIP and SAP
Router(Config)#ipx maximum-paths 2 – enables equal cost load balancing over 2 paths
Router(Config)#ipx per-host-load-share – ensures all packets to 1 destination are sent over same line
Router(Config)#int e0
Router(Config-if)#ipx network 10 encapsulation sap secondary – assigns ipx network 10 to a secondary interface on Ethernet 0 with encapsulation Ethernet_802.2
Router(Config-if)#ipx delay 6 – sets tick metric for IPX RIP (LAN = 1, WAN = 6 default)
Router(Config-if)#exit

ISDN CONFIGURATION

Router(Config)#interface bri 0
Router(Config-if)#ip address 172.17.1.63 255.255.255.0
Router(Config-if)#no shutdown
Router(Config-if)#dialer-group 1
Router(Config-if)#dialer map ip 172.16.60.2 name 8042 8350661
(Next router ip – hostname of next route (auth) – number to dial)
Router(Config-if)#dialer load-threshold 2 either – makes both interfaces come up immediately
Router(Config-if)#dialer load-threshold 255 either – only brings up 2nd B-channel if first is 100% loaded
Router(Config-if)#hold-queue 75 in – holds 75 packets in the queue during connection
Router(Config-if)#dialer idle-timeout 300 – sets idle time out (120 default)
Router(Config-if)#encapsulation ppp
Router(Config-if)#exit
Router(Config)#dialer-list 1 list 110
Router(Config)#access-list 110 permit tcp any any eq smtp
Router(Config)#access-list 110 permit tcp any any eq telnet

STATIC/DEFAULT ROUTES

Ip route 0.0.0.0 0.0.0.0 172.16.20.1 = default route
Ip default-network 172.16.1.0
Ip route 172.17.1.63 255.255.255.0 serial 1 1 permanent – keeps static route even if router cannot communicate with it, administration distance 1

CISCO DISCOVERY PROTOCOL (CDP) COMMANDS

Cdp timer 90
Cdp holdtime 240
Cdp enable (no cdp enable)

SHOW COMMANDS – 1900 SWITCH

Show mac-address-table
Show run
Show ip – like ipconfig
Show port system – shows switching method
Show vtp
Show trunk A allowed-vlans – shows which VLANS allowed on trunk link
Show vlan-membership
Show vlan 2
Show vlan – verify VLAN config
Show history – shows last 10 commands entered by default
Show terminal – shows terminal config + history buffer size

1900 SWITCH CONFIGURATION

#config t
(Config)#enable password level 1 nikolas – usermode password
(Config)#enable password level 15 makris – enable password
(Config)#enable secret nik2 – precedes the enable p/w
(Config)#hostname nik
(Config)#vtp pruning enable – enables pruning on whole switch
(Config)#delete vtp – deletes VTP database
(Config)#vtp server (client/transparent)
(Config)#vtp domain nikolas
(Config)#vtp password cisco
(Config)#ip address 172.17.1.63 255.255.255.0
(Config)#ip default-gateway 172.17.1.50
(Config)#switching-mode store-and-forward (fragment-free)
(Config)#vlan 2 name sales
(Config)#vlan 3 name marketing
(Config)#int Ethernet 0/1 – slot 0/port 1
(Config-if)#vlan-membership static 2
(Config-if)#description Finance_VLAN
(Config-if)#port secure max-mac-count 1 – allows only one mac address per port
(Config-if)#exit
(Config)#int f0/26
(Config-if)#trunk on – enables trunking of all VLANS not just VLAN 1
(Config-if)#no trunk-vlan 3 – stops trunking vlan 3
(Config-if)#duplex full – sets to full duplex (auto sense default)
(Config-if)#exit
(Config)#copy tftp://192.168.0.120/cat1900EN_9_00.bin opcode – download into flash memory
(Config)#copy nvram tftp://192.168.0.120/cat1900EN
(Config)#copy tftp://192.168.0.120/cat1900EN nvram
(Config)#delete nvram – deletes config
(Config)#delete vtp – deletes VTP database
(Config)#clear mac-address-table [dynamic]

DEBUG COMMANDS

Debug ipx routing activity – info on RIP updates
Debug ipx sap – info on sap updates
Debug ip igrp events – what’s being rec’d sent, route type (int/ext,system), source, dest
Debug ip igrp transactions – shows contents of routing updates
Debug ip rip – source/contents of updates, network, metrics
Debug frame-relay lmi – enables verification of connection
Debug ppp authentication
UNDEBUG ALL



The entire methodology to analyze and see-through the dynamics of networking within a corporate or public sector, where a series of systems are tangled with each other for access to a common network, is called network monitoring. It is basically done to ensure the proper functioning of hosting computers in accordance to their network services. This practice can be conferred as an example, at university IT networks.

Network monitoring software , specifically monitors the performance graph of devices or connections. Under any case, whether failures or errors, it detects, elicits and reports the outcome. This software places a curb over the CPU utilization of the host computers, link utilizations, and other operational aspects. One of the mediums through which it does so is that it sends certain request messages to the network of each hosts and thus ensures by measuring the responses to each requests sent.

These messages are termed as ‘watchdog messages’. If in the case of failure, slow responses or any other behavior which is unexpected, it then sends additional messages which are called ‘alerts’, to the pertinent locations such as the main server, phone number or email address to hasten up for the notion of that glitch.

Ping is one of the most commonly used software for network monitoring for simplified networks. Ping is used to send IP based test messages between the host computers. Any system (connected to a specific network) can run ping testing to ensure its connectivity and plus the overall connection performance. For intricate or professional networks, relatively sophisticated software packages e.g. HPopenview and LANdesk are used for network monitoring.

Another type of network monitoring software is focused on monitoring the availability of Web Servers. Larger enterprises which are into the usage of a broader pool of web servers and distributed world wide; this type of the software promptly acts as a sleuth, for detecting problems at any location. An expedient example for such case is ‘mon.itor.us’ which is available on the internet.

Some of the important checklists that are to monitor within the network are network tomography, route analytics, types of protocols and already mentioned; servers around the globe. Adding to this, free available network monitoring software examples are bandwidth monitor, serversAlive, sysinternals DiskMon, Sysinternals ListDLLS etc.

There are many popular software that are used to monitor the network bandwidth. These software tell you the exact utilization of your network resources.

DSL known as (digital subscriber line) basically performs a function of transferring digital data through the lines of telephone. Read it all..

Well there are numerous things when it comes to comparison of different broadband. Some of the factors that play a very crucial role are as follows: Read it all..

ADSL is a typical form of a DSL line that performs a function of faster data transmission through the copper wires as compared with a regular modem. It uses the frequencies that are not used by a telephone call and perform its function. The splitter allows a single connection to be utilized for ADSL as well as for voice calls. ADSL can be distributed at smaller distances from the main office. Usually this distance is around 4 km but can be extended to 8 km. Read it all..

There are lots of things that can be tested in a broadband speed test such as the download and the upload speed, networks, latency, DNS servers and ping time.

First most important thing that is measured in a broadband speed test is the download speed. Download speed shows how fast the connection can deliver content to your computer or the local area network. Read it all..

The basic working methodology of BROADBAND is as follows:

1. Basically the first essential thing is the modem that is used to connect and will be attached with the users personal computer.
2. Secondly if you want to connect to more than one telephone lines than a splitter is required that usually splits up the voice with the ADSL and makes sure that interference is not created at any level.
3. These splitters are than connected to the telephone wires which may be above or below ground level depending upon the location. These telephone lines are connected to a DSLAM or know as telephone exchange.
4. When the telephone line is connected to the exchange it serves the same purpose by separating the voice in the same manner as the splitter. All the DSL lines are connected to DSLAM in the telephone exchange which than passes it to multiple customers.
5. The local exchange is like a cloud because here there are multiple tons of networks.
6. The local exchange is connected to a gateway this is the point where all the terminals are terminated. There are different sizes of gate ways depending upon the traffic sizes. The most common gate ways that are being used are of 34MBS or of 155MBS. The 155MBS can support up to around 7000 customers.
7. Now the ISP is connected to the gate way. It can be connected to the gateway in different ways. There are two ways in which gateway can be connected either through an Ethernet or a gigabit Ethernet. Like for example if your ISP is of around 155MBS than Ethernet wont work the only thing that will work in such case is the gigabit Ethernet.
8. Once your ISP is connected the BROADBAND is in proper working condition.

The ordinary phone lines normally can transfer fewer amount of data from one place to another which is around 29.6kbps but as the time passed on consumers demanded a much faster and easier way for speedy data transmission so broadband fulfilled that purpose.

So if the ordinary telephone line has a single channel to carry data at the same time broadband has the ability to carry multiple channels hence transferring data at a higher speed. It’s just like a tunnel the broadband is a big tunnel that allows flow of information and telephone is a small tunnel that allows less amount of information flow.

Wireless router is basically used in the wireless internet connections which perform basically two functions:

• Router
• Access point

The basic function of the router is that it allows the information to go forward without the need of cable device. Mostly the wireless routers have following properties/characteristics:

• A LAN port to connect to a local area network.
• A WAN to connect to the wide area network.
• Wireless antenna which allows connecting to different connections.

Wireless routers basically have wired as well as wireless routes so that consumer can have wired as well as wireless connectivity at the same time. Following things should be kept in mind before buying a wireless router:

1. Mostly look for dual band routers because they perform much better than the single band routers.
2. You can also use simultaneous routers but that can be expensive.
3. Don’t go for two or three antennas the most important thing is the router.
4. Usually go for a router that has a guest access which can allow your friends to have an access without telling them the network password.
5. Always look for WIFI protected set up because it provides you maximum protection.
6. Mostly all the wireless routers have a firewall so there is no need of extra firewall protection except in few cases.
7. Always do activate a DNS account in your router.

The most basic function that the router performs is the traffic that it manages at your home. The router should always be placed closed to the signaling device. Routers can be used to increase the strength of the signals by placing it properly.

It is always important to buy antennas from the same person who is providing the router so that it matches the specifications. In order to attach more that one router make sure the there is no sort of disturbance in the installation process. Some technologies can now convert a wireless router in a converter these are very common like for example DD-WRT can convert a wireless router into a converter.

The most recent technology these days is the wireless broadband which allows an internet access and transfer of data to a much larger extent. Most wireless broadband have an access facility of around 50km. initially the wireless internet facility was being adopted in the rural areas where it was very difficult for DSL to reach.

To simply use the wireless internet service the consumer’s just place a dish or some sort of signal catcher in front of the transmitter that provides the signal and passes it through to the consumer. Basically the wireless modem receives the services and than convert these services into radio signals so if a consumer is connected in that area signals are transmitted to him.

Most commonly the wireless internet is being used in laptops the only thing required is the broadband adapter. What happens is that the adapter once connected starts searching for wireless signals and when it catches the signals it tries to connect it self with it.

If there is no security protection than their would be an easy connectivity between the two. Mostly the wireless broadband is protected with some sort of security otherwise customers would just use the facility and increase the customer traffic. To avoid such thing now a days high security software’s are used to protect unknown users from connecting the wireless internet facility.

Wireless broad band makes it much easier for the users to use the internet. Simply following things are required to connect through a wireless network:

• Wireless modem
• Router
• Switch

Wireless broadband is very common now days and is being used by large organizations as well as chain hotels. The basic workable function of wireless broadband is that a consumer connects itself through some sort of a signal catcher or a transmitter. The transmitter catches the signals in the form of radio signals and than it passes it through to the router and than to the modem. The modem than connects the consumer with the transmitter.

In early phases DSL was most commonly known as digital subscribers loop but since it has gained lots of popularity it is now known as digital subscribers line. The basic function of DSL is that it provides digital data to pass through the lines of telephone. DSL has this unique property that it can be used with the telephone line without disturbing it. This unique property is due to the fact that DSL usually uses very high frequency while the ordinary telephone operates at a low frequency as compared with the DSL. The performance of DSL depends upon two things:

1. What service level is adopted?
2. What is the condition of line?

The working of DSL is basically in two very simple steps. DSL divides the frequencies that are used in a telephone in to two parts. First is the ISP data which is carried through the higher frequency and the second which is most important is the voice which is carried over through the low frequency. This is the only reason the DSL modem and the telephone lines can be used together. The basic working of the DSL is as follows:

• First of all DSL modem is attached to the customer’s phone line.
• Now the telephone company connects the other part of the telephone line to what is called as DSLAM.
• When the DSL modem is switched on it does a self test.
• It normally checks the connection between the DSL modem and the sender.
• In the last phase the DSL modem tries to synchronize with the DSLAM.

The basic function of the DSL modem is that it converts the digital data into small voltage signals that can be used in the phone lines. In very few cases some DSL do require some sort of filters to be installed. These filters are installed at the telephones near the customer residence. There are lots of digital subscribers technologies like:

1. ISDN
2. HDSL
3. SDSL
4. ADSL
5. ADSL2
6. ADSL++

DSL carries a download speed from around 256kbit/s to almost around 28000kbit/s and it varies.DSL is the latest technology that is being used for high speed connectivity and optimum performance.

Broadband these days is very widely used in telecommunication these days. Its basic function consists of providing signals by handling wide range of frequencies. These frequencies can be than subdivided into frequency bins. It has a very simple working principle the larger is the bandwidth larger amount of information it can carry. Broadband is used in several different areas for example:

1. Telecommunication
2. Data communication
3. DSL
4. Ethernet
5. In power line communication
6. In video

In data communication broadband serves as source to handle numerous pieces of data to increase what is called the transmission rate. The basic function of broadband in DSL (digital subscriber line) is that it can transfer the digital information to a very high bandwidth channel. The common interface that is used for the broad band modems is the Ethernet which is used for DSL as well as cable net. Now a day’s power line communications are also being used.

So the basic function that the broad band performs in the power line communication is to achieve very high data rates. The basic difference between broadband and the dialup is that the dialup modems are limited to bit rates while broadband provides much greater speed without disturbing the telephone line. Now why broadband is called high speed internet because it has the ability to transfer data at a very high speed. Basically broadband is anything higher than 256kbit/s.

The common term that is used in broad band is data rates. Data rates are typically defined as maximum number of download. Broadband technologies which are common in most areas are DSL and cable modems. Many newer technologies are coming up like VDSL and optical fiber. In most of the areas where people face a difficulty to install DSL or cable modems they are using what is called as WIFI.

Broadband is very commonly used these days in mobile networks other than the computers. The technology that is used in mobile networks is called as WIMAX. There is no set definition regarding broadband with respect to bandwidth but mostly anything above 786kbit/s is considered as broadband. So broadband plays a very vital role in telecommunications and is spreading at a very high pace all over the world.

How Do I Setup My Own Home Network

You can setup or connect the home computers to share files, share printers, share broadband Internet access, and play network games and a lot of other resource sharing.  Before setting up the network you must be clear for what purpose you want to configure or build your network. Following are the types of the home network that can be setup:

Peer-to-Peer network
Basic Ethernet network with file sharing
Basic network with file and modem Internet sharing
Basic network with file and broadband Internet sharing

We will setup the home network by using the Peer-to-Peer topology

Peer-to-Peer network

Advantages of Peer to Peer Network:

Connect two commuters quickly and easily.
Can share files, play network games.

Disadvantages:
Generally one or two or limited amount of computers can be connected to network

Estimated Time to Setup:
15-20 Minutes

Hardware and Software Required:
- 10/100 Ethernet network cards installed in two computer and in working condition.
- A Network cross-over cable of suitable length.

Steps for Windows 95 and Windows 98:

1. Check device manager that network cards are properly installed and latest set of drivers are installed for that network cards.
2. Physically connect two computers with a cable.
3. Go to the Network properties. Just click Start / Settings Control Panel and double-clicking “Network”.
4. Verify that both IPX/SPX and TCP/IP are installed for your network adapter. If one of them is not installed first install them from the CD.
5. After the protocols have been installed, go to the Network window click the “File and Print Sharing” button. Here you specify whether to give the print and file sharing or not. This has to be done for each computer connected on the network.
6. Now setup the TCP/IP protocol for the network adapter and clicking the “Properties” button.
7. Select the option “Specify an IP address” within the properties. Enter any value as shown belowIP Address: 102.55.92.1
   Subnet Mask: 255.255.255.192
8. The IP address differs from computer to computer. For the other computer the subnet mask can be the same but the ip address will be 192.55.92.2
9. Now when all the things have completed successfully just reboot your computer and the home network is installed.

Steps for Microsoft Windows ME, 2000 and XP:

1. First step is the same to verify that network card are inserted and installed properly.
2. Now connect the two or more computers to each other.
3. Launch the Network properties by clicking Start menu / Settings / Control Panel and double-clicking “Network and Dial-up connections” option.
4. Make a Double-click on the “Local Area Connection” icon and click the properties button.
5. Carefully verify that IPX/SPX and TCP/IP are installed for your network adapter. First install it if it is not present.
6. In the next step choose if you want to enable the file and print sharing with other computers.
7. Now setup the TCP/IP protocol for the network adapter and then click the “Properties” button.
8. Specify the ip address. You can enter the values similar to the one shown belowIP Address: 102.55.92.1
   Subnet Mask: 255.255.255.192

   Subnet mask will be the same but IP address will be different for all the computers.

9. Once all the steps are performed correctly make a reboot of the system and the home network is now ready.