Top Five Questions and Answers

Top Five Questions and Answers

1. Differentiate User Mode from Privileged Mode

A. User Mode is used for regular task when using a CISCO router, such as to view system information, connecting to remote devices, and checking the status of the router. On the other hand, privileged mode includes all options that are available for User Mode, plus more. You can use this mode in order to make configurations on the router, including making tests and debugging.

2. What is 100BaseFX?

A. This is Ethernet that makes use of fiber optic cable as the main transmission medium. The 100 stands for 100Mbps, which is the data speed.

3. Differentiate full-duplex from half-duplex.

A. In full-duplex, both the transmitting device and the receiving device can communicate simultaneously, that is, both can be transmitting and receiving at the same time. In the case of half-duplex, a device cannot receive while it is transmitting, and vice versa.

4. What is MTU?

A. MTU stands for Maximum Transmission Unit. It refers to the maximum packet size that can be sent out onto the data line without the need to fragment it.

5. What is latency?

A. Latency is the amount of time delay that measures the point from which a network device receives a data frame to the time it sends it out again towards another network segment.

What causes CRC errors?

What causes CRC errors?

A. Cisco networking CRC errors are generally a layer 1 issue caused by a faulty port on the device or bad Ethernet cable. Changing the cable or swapping the port is a relatively easy fix. Occasionally they are generated on layer 2 by a duplex mismatch. This happens when the port on one device is set for full-duplex and the port on the connected peer device is set for half-duplex.
The ports can be compared by using the show interface command on both devices.
In TDM networks, there are many problems that cause CRC errors. They include faulty wiring or cross-connects, bad repeater cards, flakey smart jacks, or bad cable and channel cards. Isolating the cause of these errors usually requires the telecommunications provider to conduct loopback testing or to dispatch a field engineer to the site to test head-to-head with the central office.

I am Creating Multipal Groups

Microsoft Team                          https://chat.whatsapp.com/570e37NqCki86YBIsPch8I

RED HAT Team                          https://chat.whatsapp.com/9Z1CEAj6WUg2wfuZoHVH5l

CISCO Network Team                 https://chat.whatsapp.com/3StK3uPqgQUJ3Yk02YYT0A

Question of The Day

Question of The Day

TOP FIVE QUESTIONS AND ANSWERS OF CISCO

What is CISCO?

How to Enable SSH on Cisco Switch, Router and ASA

How to Enable SSH on Cisco Switch, Router and AS

 I have a Cisco switch and Router  in my network, which I can access by hooking up a console cable directly to the device. I like to access the switch remotely using SSH. How can I enable SSH 

By default, when you configure a Cisco device, you have to use the console cable and connect directly to the system to access it. Follow the steps mentioned below, which will enable SSH access to your Cisco devices. Once you enable SSH, you can access it remotely using PuTTY or any other SSH client.

1. Setup Management IP

First, make sure you have performed basic network configurations on your switch. For example, assign default gateway, assign management ip-address, etc. If this is already done, skip to the next step.

In the following example, the management ip address is set as 192.168.101.2 in the 101 VLAN. The default gateway points to the firewall, which is 192.168.101.1

# ip default-gateway 192.168.101.1

# interface vlan 101
(config-if)# ip address 192.168.101.2 255.255.255.0

2. Set hostname and domain-name

# config t
(config)# hostname myswitch
(config)# ip domain-name thegeekstuff.com

3. Generate the RSA Keys

The switch or router should have RSA keys that it will use during the SSH process. So, generate these using crypto command as shown below.

myswitch(config)# crypto key generate rsa
 The name for the keys will be: myswitch.thegeekstuff.com
 Choose the size of the key modulus in the range of 360 to 2048 for your
   General Purpose Keys. Choosing a key modulus greater than 512 may take
   a few minutes.

How many bits in the modulus [512]: 1024
 % Generating 1024 bit RSA keys, keys will be non-exportable...[OK]

4. Setup the Line VTY configurations

Setup the following line vty configuration parameters, where input transport is set to SSH. Set the login to local, and password to 7.

# line vty 0 4
(config-line)# transport input ssh
(config-line)# login local
(config-line)# password 7
(config-line)# exit

If you have not set the console line yet, set it to the following values.

# line console 0
(config-line)# logging synchronous
(config-line)# login local

5. Create the username password

If you don’t have an username created already, do it as shown below.

myswitch# config t
Enter configuration commands, one per line.  End with CNTL/Z.
myswitch(config)# username ramesh password mypassword

Note: If you don’t have the enable password setup properly, do it now.

myswitch# enable secret myenablepassword

Make sure the password-encryption service is turned-on, which will encrypt the password, and when you do “sh run”, you’ll seee only the encrypted password and not clear-text password.

myswitch# service password-encryption

DHCP relay agent

Specifying the Packet Forwarding Address

Perform this task to configure the DHCP relay agent to forward packets to a DHCP server.

SUMMARY STEPS

1.    enable 
2.    configure terminal 
3.    interface type number 
4.    ip helper-address address 

Delivery schemes

DELIVERY SCHEMES

Routing schemes differ in how they deliver messages:

·        Unicast delivers a message to a single specific node

Unicast

·        Anycast delivers a message to anyone out of a group of nodes, typically the one nearest to the source

Anycast

·        Multicast delivers a message to a group of nodes that have expressed interest in receiving the message

Multicast

·        Geocast delivers a message to a geographic area

Geocast

·        Broadcast delivers a message to all nodes in the network

Broadcast

Unicast is the dominant form of message delivery on the Internet. This article focuses on unicast routing algorithms.

Data link layer

Data link layer:

This layer will convert data packets into data frame and also this layer works with it two sub layer

1)      MAC (media access control ){ Bus, Ring, Star }

2)      LLC (logical link control ) { EX- Ethernet, fast Ethernet, GBE }

Five steps of data encapsulation – TCP/IP

Five steps of data encapsulation – TCP/IP

Data Application layer

TCP Data Transport layer

IP TCP Data Internet layer

LH IP TCP Data LT Network interface

Transmit bits

TCP/IP Architecture model and example protocols

TCP/IP Architecture model and example prot ocols                              

TCP/IP (DOD)	OSI MODEL	Example protocols
Application	Application	telnet,  HTTP, FTP, WWW, Gateway(Eudora, cc:mail), SNMP
	Presentation	JPEG, ASCII, EBCDIC, TIFF, GIF, Encryption, MIDI, All Extension
	Session	RPC, SQL, NFS, NetBIOS names, AppleTalk, ASP, DEC net, SCP
host to host	Transport	TCP, UDP, SPX
Internetwork	Network	IP, IPX, Apple Talk DDP
Network interface	Data link	IEEE 802.3/2, HDLC. Frame Relay, PPP,FDDI, ATM,IEEE
	Physical	EIA/TIA-232, V.35, RJ-45,Ethernet,802.3, 802.5

Cisco Revs CCNA R&S Cert (V3.0)

Cisco Revs CCNA R&S Cert (V3.0); Leans Forward

Yep, it’s official. Cisco just announced (May 17, 2016) big changes to the #CCENT and #CCNA, that is, the Cisco Certified Entry Network Technician (CCENT) and Cisco Certified Network Associate (CCNA) Routing and Switching certifications. As with any big change, there are new exams, exam numbers, and changes to the exam topics. This post gives the overview, some links, and a promise of more posts in the next few days.

Exam Structure Unchanged, But Exam Numbers and Cert Names Change

First off, when Cisco makes a big announcement about one of their certifications, many aspects of the certification can change. Cisco always changes the exam numbers, and they always change the exam blueprint (the document that lists all the exam topics). They could also change details like the number of exams you must take, or even remove an old certification or replace it with a new certification.

For these May 2016 announcements for the CCENT certification and the CCNA Routing and Switching certifications, Cisco changed only the exam numbers and the exam blueprint details for those exams. No program details were changed. Simple enough.

To briefly review you have two options: pass both the ICND1 and ICND2 exams, or pass the CCNA Routing and Switching exam. With the new exam transition, you can pass a combination of old and new. (For CCENT certification, you just have to pass the ICND1 exam.) Figures 1 and 2 list those paths, along with the new exam numbers introduced in 2016.

Figure 1: Exam Path to CCENT (New Exam, May 2016)

Configure Inter-VLAN Routing

Configure Inter-VLAN Routing on Cisco Routers and Switches

AUGUST 21, 2016 AT 12:17 PM

Here is an additional resource from Chapter 8 – Routing Fundamentals – Inter-VLAN Routing chapter of my upcoming ICND1 Exam Cram!

TCP/IP Architecture model and examples of protocols

TCP/IP Architecture model and example protocols                              

                           

TCP/IP (DOD)	OSI MODEL	Example protocols
Application	Application	telnet,  HTTP, FTP, WWW, Gateway(Eudora, cc:mail), SNMP
	Presentation	JPEG, ASCII, EBCDIC, TIFF, GIF, Encryption, MIDI, All Extension
	Session	RPC, SQL, NFS, NetBIOS names, AppleTalk, ASP, DEC net, SCP
host to host	Transport	TCP, UDP, SPX
Internetwork	Network	IP, IPX, Apple Talk DDP
Network interface	Data link	IEEE 802.3/2, HDLC. Frame Relay, PPP,FDDI, ATM,IEEE
	Physical	EIA/TIA-232, V.35, RJ-45,Ethernet,802.3, 802.5

Difference Between TCP and UDP Protocols

Transport layer:

This layer is responsible to deliver the data from one host to another host computers and there for good be perform in first will be deliver two different ways. (Fragment is called segment)

1)      TCP

2)      UDP

TCP

·         It is reliable and Connection  oriented 

·         It create Virtual circuit between the host

·         Its provide sec Vance number for each Segment of the data

·         It support Retransmission and always get acknowledgement  for each segment

·         It support Flow control over the data 

·         It support Windowing 

·         Its Slow

UDP

·         Connection less and non-reliable

·         No virtual circuit

·         No segment

·         No retransmission

·         No flow control

·         No windowing
      Fast 

Career In Computer Networking

Be a Computer Network Engineer: Step-by-Step Career Guide

Research the requirements to become a computer network engineer. Learn about the job description and duties, and read the step-by-step process to start a career as a computer network engineer.

Should I Become a Computer Network Engineer?

Computer network engineers, also known as network architects, plan and construct data communication networks, such as local area network (LAN) and wide area network (WAN) systems. This can involve selecting the hardware and software, determining the layout of cables, and overseeing other IT professionals to create networks.

The majority of computer network architects work full-time, although overtime is common. Few physical demands and risks are associated with this career. Such computer architects spend long periods of time in front of computers.

Career Requirements

Degree Level	Bachelor's degree required, though some employers prefer Master of Business Administration (MBA) degrees
Degree Fields	Computer science, information systems or computer engineering
Certification	Voluntary certification is available through software companies like Microsoft and Cisco
Experience	5-10 years working in network administration usually required
Key Skills	Analytical and problem-solving skills, aptitude for creativity and design, customer-service skills, the ability to lead a team, knowledge of mathematics, telecommunications and electronics, ability to use analytical, network security, network monitoring and administration software programs, familiarity with network analyzers, network switches and wireless LAN servers
Salary (2016)	$120,800 yearly (mean for computer network architects)

• Complete an internship. Experience is essential to entering this career, and so aspiring computer network engineers may benefit from completing internships to gain practical experience in the industry. In fact, some bachelor's programs offer internships to network engineering students. Some individuals may find that their schools instead offer cooperative learning experiences, which similarly allow the opportunity to gain hands-on experience while earning college credit.

• Earn industry-standard certifications. Software vendors such as Microsoft, Cisco and Red Hat offer certifications to network administrators who use their products after passage of an exam. Possessing one of these certifications may enable individuals to advance in their careers faster, and some employers even require administrators to be certified in specific programs.

.

Step 1: Earn a Bachelor's Degree

While a bachelor's degree in general computer science will suffice, many schools offer 4-year degree programs specifically in network or computer engineering. These programs provide an overview of standard industry networking tools and procedures for resolving problems within computer networks. Classes cover topics like operating systems, programming essentials, network administration and information security. Students may also gain instruction in specific networking systems, like Cisco.

Success Tip:

Step 2: Work as a Network Administrator

The U.S. Bureau of Labor Statistics (BLS) reports that many network engineers are promoted from network administration or other similar IT positions. Network administrators mostly focus on installing, maintaining and monitoring the performance of networks, as well as overseeing IT support specialists, and they may assist engineers in the network design process. After earning at least five years of experience and demonstrating proficiency in networking, these workers may advance to network engineer status.

Success Tip:

Step 3: Consider Earning a Graduate Degree

The BLS notes that some employers favor network engineers who possess graduate degrees, such as an MBA with a focus on information systems. These MBA programs typically last two years and combine instruction in business topics with instruction in IT concepts. Master of Science in Computer Networking degree programs are also available. These programs include classes in wireless networking, telecommunications design and Internet protocols.