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Cisco DNA Center Vs Arista Cloud Vision

Today I am going to talk about the Automation orchestration layer for Cisco and Arista which can push the policies around the network automatically and many other features to have the best customer experiences. The goal for Cisco and Arista are same to provide the automation in the Campus or enterprise networks.

Before I will start up with the Cloud Vision and Cisco DNA center, I would like to tell you guys that we have our own youtube channel for various network videos that can further help you guys to study further. I will going to add many more videos soon on the channel, Please subscribe to the channel for the study network related videos.

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Arista Networks- Cloud Vision
Lets talk about the Cloud Vision first. Cloud Vision is the part of Arista Networks showing the capabilities of the network automation.

CloudVision platform is a software suite of services that deliver further operational simplification of the Arista physical infrastructure 

Work ow monitoring and provisioning is controlled centrally with pre-integrated tool sets for provisioning, change management, network-wide upgrades & rollback, network monitoring, network virtualization, and visibility services. 

Fig 1.1- ARISTA Cloud-Vision

CloudVision actually Continue reading

Introduction to Arista Networks High End Switches : Arista 7500 E Switches

Today I am going to talk about one of the new vendor in the market named as Arista Networks who came up with the high end Switches. Although Arista Networks have many switches in their portfolio but specifically I am going to talk about the Arista 7500E switches.

Before I start with the Arista 7500E switch, I would like to tell you guys that we have our own youtube channel for various network videos that can further help you guys to study further. I will going to add many more videos soon on the channel, Please subscribe to the channel for the study network related videos.

Subscribe us on Youtube:

Arista 7500E come up with two different models. These switches are generally for the core switching as they have the high switching capacity. These models are Arista 7504E and Arista 7508E. Arista 7500E Series modular systems are high performance data center switches, available in a compact 7RU (4-slot) or 11RU (8-slot) they combine scalable L2 and L3 forwarding and traffic management with advanced features for network monitoring, precision timing, and network virtualization to deliver deterministic network performance for mission critical data centers, cloud computing, enterprise and HPC environments.

Arista Continue reading

Interoperability between Dell and Cisco: Rapid-PVST+

Today I am going to talk about the PVST+ as many of you already know. PVST+ is the advance version of PVST and stands for the Per VLAN spanning Tree Plus. As the name suggest you can have the you are creating STP for the VLANs. So if you have 3 VLANs in your network you have 3 different STP instances per VLAN in your LAN network.

Before I start with the PVST+ ,I would like to tell you guys that we have our own youtube channel for various network videos that can further help you guys to study further. I will going to add many more videos soon on the channel, Please subscribe to the channel for the study network related videos
Subscribe us on Youtube:

Here today I am taking an example where i am taking Cisco and Dell switches in a LAN network and we are going to check the interoperability between the Cisco and Dell. 

Below is the sample network topology showing the Cisco and Dell switches 
Fig 1.1- LAN network STP topology
So in the above mentioned topology, we have 2 Cisco 3550 switches and connected with the Dell Force10 S60 switch Continue reading

Basic Router Configurations on Cisco Router

Today I am going to talk about the basic configurations on Cisco routers where i can define the basic commands like setting console password, assign VTY password, configuring IP addresses on the interfaces, Configuring the router for SSH access, Configuring basic IPv6 configurations on the router, configuring trunk based inter-VLAN routing, configuring IPv6 configurations manually and at last configuring OSPFv6 with the use of IPv6.

This is a basic article for the starters who are going to configure the router from the scratch. Most of the basic configurations are for demo purposes and you can use your IP addresses as per requirements in your network. Lets start with the basic configurations on the router now.

Fig 1.1- Basic Network Topology
Above is the basic network topology where we have 3 layer architecture with the Cisco ASA firewalls and the routers. We are going to configure WAN routers with the basic configurations

Configure the Basic router 
Router> enable
Router# config terminal 
Router(config)# hostname ttlbits_ttlbits_R1
ttlbits_R1(config)# no ip domain-lookup 
ttlbits_R1(config)# security passwords min-length 10 
ttlbits_R1(config)# enable secret cisco12345 

Now let's configure the console password on the Cisco routers, below is the basic example showing the configurations of console on router.

Configuring vPC on Cisco Nexus Devices

Today I am going to talk about the configurations of vPC on Cisco Nexus devices as i already talked about vPC in my earlier articles. If you want to have a look on the vPC basics check the below mentioned link for your references.

A short Story on vPC- Virtual Port Channel in Cisco Datacenter Environment

There are lot of questions how and why we are using the vPC in the Datacenter environment while some asked me about the difference in the vPC and VSS. Please have a look on the below link for the comparison of vPC and VSS.

Features comparison : Cisco vPC and Cisco VSS

Apart from the above mentioned articles, I wrote on the different technologies used by other vendors same as Cisco uses vPC and VSS. Below is the link defining the same

Feature Comparison: Juniper VCF vs HP IRF vs Cisco VSS vs Cisco vPC

From all the above articles, I think now you got the basics on vPC and VSS, but in this article I will talk about the vPC configuration in details with the diagram. The topology used in the article will be sample topology and has no relevance with any of Continue reading

Introduction to Network Time Protocol (NTP) and Basic Configurations

Today I am going to discuss about the NTP or so called Network Time Protocol. I knew many of you already aware about the use of NTP in our networks but as it was asked by some guys who follow our blogs, So I am happy to explain the NTP little bit with the configurations.

What is Network Time Protocol or NTP ?
So, NTP is Network Time Protocol which is generally used to synchronise of the devices to some specific time references. NTP uses UDP protocol to communicate with all the devices in the network and all NTP communications in the network will be synchronised with the defined universal time in the network.

How they synchronise with the time source ?
NTP server usually receives its time from a trustworthy time source, such as a radio clock attached to a time server, and then distributes this time across the network. NTP is extremely efficient and there is no more than one packet per minute is necessary to synchronize two machines to within a millisecond of each other

An Network Time Protocol actually uses a layer to describe the distance between a network device and an authoritative time source

Introduction to Point to Point Authentication : PAP and CHAP protocols

Today I am going to talk about the PAP- Password Authentication Protocol and CHAP- challenge handshake authentication protocol. So let's talk about PAP and CHAP one by one.

PAP and CHAP is one of the basic and most important topic for CCNA candidates or the freshers who are going to work on the Point to point networks.

Before we are starting with the PAP and CHAP protocols, I would like to tell you that PAP and CHAP is the authentication procedure in Point to point network. So if you are using Point to point networks in your architecture you should opt for PAP or CHAP protocols as per the design required.

Below is the example showing the pictorial representation where we are defining the acceptance and the refusal of the connection in both the cases.

PAP- Password Authentication Protocol
So PAP is a password-based authentication protocol used by Point to Point Protocol (PPP) to validate users. PAP generally consider as a very basic two-way process. There is no encryption. The username and password are sent in plain text. If it is accepted, the connection is allowed. 

The authentication phase of a PPP session is optional. If used, you can authenticate the Continue reading

Introduction to ACI Multi-Site Fabric Design Network

In my earlier post I talk about the ACI stretched Fabric and ACI multi-pod fabric designs with single and multiple APIC clusters. Now I am going to talk about the basics of the Cisco ACI Multi-site fabric design network in my article. If you want to have a look for my earlier article, please go through the below mentioned link and review before we will start with the Cisco ACI multi-site fabric network design.

Introduction to Cisco ACI stretched fabric and ACI Multi-pod Fabric Designs

So in short, you now understand the Cisco single-pod, Cisco ACI stretched fabric and Cisco ACI multi-pod fabric design. Now we are going to talk about the next level of Cisco ACI deployment model and this model is called as Cisco ACI Multi-site fabric design.

Cisco ACI Multi-site Fabric Network Design 
Making more innovation in the Cisco ACI with the APIC 2.0 release, Cisco said that a Multi-Site design is the architecture interconnecting multiple APIC cluster domains with their associated pods. 

A Multi-Site design could also be called a Multi-Fabric design, because it interconnects separate availability zones (fabrics), each deployed either as a single pod or multiple pods (a Multi-Pod design). Below is Continue reading

Introduction to Cisco ACI stretched fabric and ACI Multi-pod Fabric Designs

Today I am going to talk about Cisco ACI where Cisco is providing two different solutions on Cisco ACI. One solution is Cisco ACI Multi-pod and other solution is named as Cisco ACI Multi-Site design or architecture. 

Earlier Cisco ACI multi-pod environment we were doing the ACI stretched Fabric design but then Cisco come up with the solution called as Cisco ACI multi-pod.

What is Cisco ACI Multi-pod ?
Well ACI multi-pod is a kind of ACI stretched Fabric design with more benefits and features. In simple words we can say that ACI multi-pod is a multiple ACI fabrics that is under control of single management or administration. 

What is the key difference of ACI stretched fabric design and ACI multi-pod ?
Let's talk about the ACI stretched fabric design, Let us suppose we have two ACI fabric design where we have Spine-Leaf architecture. One is ACI-I and other is ACI-II, if you are going to connect the leaf switches of ACI-I with the spine switches of ACI-II and leaf switches of ACI-II with spine switches of ACI-I makes ACI Stretched fabric design. Below diagram shows the best way of Cisco ACI stretched fabric design between three ACI fabric networks.
Continue reading

Fortinet Next Generation Firewalls : Fortinet 5000 Series Firewalls

Today I am going to talk about Fortinet Next Generation Firewalls. As i already wrote many articles on Next Generation firewalls. Below are some of the links of other vendors describing Next Generation Firewalls

Above are some of the articles i wrote about Firewalls on different vendors which includes Cisco, Sophos, Checkpoint, Symantec, Meraki and Palo-Alto.

Now I am going to talk about the Fortinet Next Generation Firewalls.

Fortinet Next Generation Firewalls
The Fort iGATE High-end series of Data Center and Next-Gen Firewalls deliver all the top-rated security effectiveness you expect from Fortinet, in an ultra-low latency compact appliance and flexible chassis platform. 
Fig 1.1- Fortigate Next Generation Firewalls

Purpose built Forti-ASIC processors and FortiOS, delivers exceptional throughput and enables security, scalability, flexibility and manageability you demand for data center edge Continue reading

Quick Facts on EIGRP

Today, i am going to discuss about the one of the important Cisco routing protocol in many of the enterprise domain network. EIGRP is now open source routing protocol and can be used by any vendor.

The Protocol is initially Cisco Propriety  protocol but later on Cisco announces this protocol as open standard protocol and is now used in any of the routers ( It can be Juniper, Huawei, HP or any other ). 

There are lot of interesting facts around the EIGRP protocol, Some says it is Link state routing protocol and some says it is distance vector routing protocol. Well it is a Hybrid routing protocol. I am expecting you guys know about the fact of Distance Vector routing protocol and also know about the features and working of the Link State routing protocols.

I already wrote about the distance vector routing protocol and Link State routing protocol below is the link for your reference

Now talk about the distance vector routing protocol.Whenever there is discussion on Distance vector routing protocol then there are two protocols and they are RIP ( Routing Information Protocol ) and IGRP Continue reading

Cisco PIX Security Appliances Firewall modes

Today I am going to talk about the different modes of Cisco PIX firewall. By default if you talk about the mode of the firewall, a firewall is a routed hop and acts as a default gateway for hosts that connect to one of its screened subnets. 

In recent years, a growing best practice has been to deploy firewalls not only at the traditional network perimeter-where the private corporate network meets the public Internet-but also throughout the enterprise network in key internal locations, as well as at the WAN edge of branch office networks. This distributed-firewall strategy helps protect against internal threats, which have historically accounted for a large percentage of cyber losses, according to annual studies conducted by the Computer Security Institute (CSI).

Now let's talk about the different firewall modes. There are two modes of firewalls and they are as routed mode and transparent mode.

Cisco PIX Security Appliances Routed mode
Default mode of an ASA. The ASA acts as a single firewall and all interfaces are provisioned to be managed through a single firewall configuration.

Fig 1.1- Firewall Routed mode
Configuration Example for Cisco PIX security appliances in routed mode

Below is the basic way Continue reading

Alcatel-Lucent (Nokia) 7750 Service routers

Today I am going to talk about the Alcatel-Lucent 7750 Service routers as they are very much robust in nature and in demand with many of the enterprise networks. Now the Alcatel-Lucent 7750 Service routers are now rebranded and renamed as Nokia 7750 Service routers. The Nokia 7750 service routers are delivers the performance, service richness, and intelligence to drive the converged IP network edge.

The Alcatel-Lucent 7750 service Router (SR) portfolio is a collection of multi-provider edge routing structures that supply high performance, carrier richness, and creates first-rate value for networking in the cloud generation. it's far designed for the concurrent delivery of advanced residential, business and Wi-Fi broadband IP offerings, and gives cloud, records middle and department office connectivity for corporation networking on a commonplace IP part routing platform.

Fig 1.1- Alcatel-Lucent/Nokia 7750 service Routers

Leveraging Alcatel-Lucent 400 Gb/s FP3 silicon technology and a comprehensive suite of IP/MPLS routing capabilities, the 7750 SR has the flexibility to be deployed in a wide range of applications:
  • Broadband network gateway for residential service delivery with advanced subscriber management
  • Multiservice edge router for business VPN/Internet access, cloud and data center interconnect services
  • Enterprise router providing intelligent connectivity to the Continue reading

Cisco Firepower 4100 Series introduction

Today in this article I am going to talk about the Cisco Firepower 4100 series. As in my earlier articles I talk about the Cisco Firepower 2100 series and Cisco Firepower 9300 series which is one of the most powerful box in security domain.

Before we start with the Cisco 4100 series Firewall, A next generation firewall with NGFW image, below are the Cisco Firepower 2100 and Cisco Firepower 9300 articles. You can go to that articles as well for your references.

Cisco Firepower 9300 Series
Cisco 2100 Series Firepower
Cisco Firepower 2100 BOQ guide

Cisco Firepower 4100 Series is a family of four threat-focused NGFW security platforms. Their throughput range addresses data center and internet edge use cases. They deliver superior threat defense, at faster speeds, with a smaller footprint.  

Fig 1.1- Cisco Firepower 4100 Series

Cisco Firepower 4100 Series supports flow-offloading, programmatic orchestration, and the management of security services with RESTful APIs. Network Equipment Building Standards (NEBS)-compliance is supported by the Cisco Firepower 4120 platform.

Cisco Firepower 4100 series comes in various models and these models are 
  • Cisco Firepower 4110
  • Cisco Firepower 4120
  • Cisco Firepower 4140
  • Cisco Firepower 4150
Let's talk about the basic features of Continue reading

Cisco Firepower 9300 Series Introduction

Today I am going to talk about the Cisco Firepower 9300 series which is one of the most powerful box by Cisco systems. Cisco Firepower 9300 is a Next Generation Firewall and has various capabilities of AVC, IPS, AMP and URL filtering with the high throughput value.

Cisco Launches 3 different series in the Firepower services which is called as Next generation Firewalls with all the above mentioned services within a box. The Firepower series are
In this article, I will only talk about Cisco 9300 Firepower next generation firewalls. Although you can have two different images in the box. You can use ASA image or NGFW image in all these 3 boxes as per the requirement in your network. 

Cisco Firepower 9300 is a highly scalable with carrier-grade, modular platform designed for service providers, high-performance computing centres, large data centres, campuses, high-frequency trading environments, and other environments that require low (less than 5-microsecond offload) latency and exceptional throughput. 

Fig 1.1- Cisco Firepower 9300 NGFW

Cisco Catalysts Supervisor Engines,Interfaces and Modules- Cisco 6500 and Cisco 6800

Today I will talk about the Line cards in the Chassis and explain you where to use which line card and how we design the network with the user count. People asked me so many questions on the line card part and they are always confuse about the use of the line cards in the chassis. The article is based on the Cisco devices where we are using the line cards to accommodate the users in the network at the access layer and to have the smooth traffic flow.

Below image shows the two different Chassis in VSS format where we connect the chassis back to back with the SUP engines. The SUP can be 2T or 6T depends upon the requirement and the design of the campus or enterprise network.

Fig 1.1- VSS using SUP Engines

Let's talk about one by one in details, First I will talk about the Supervisor Engines 6T and 2T. I will not talk about the previous SUP engines as they are going or they are already at the verge of end of sale/support.


C6800-SUP6T : This is a Supervisor Engine SUP6T with with 8 ports 10GbE, 2 ports 40GbE and Continue reading

Discussion about SFP, SFP+, QSFP, QSFP+, XFP and CFP Modules/Connectors

Today I am going to talk about the hardware generally used in many of the devices for the fiber/copper connectivity with the devices in the network.

I will talk about the various kinds of modules which includes the following types

  • SFP
  • SFP+
  • XFP
  • CFP
Fig 1.1- Sample QSFP+ to SFP+ Connectivity

Lets start with the SFP module discussion, then we will go with the SFP+, QSFP, QSFP+, XFP and then CFP modules. I will talk about the usage, Wavelength, data rate speed and so many factors which describe these modules in details. I hope with this article you will easily understand the various types of modules uses in industries now a days with the capacity and the data rate speed of these different modules.

SFP: SFP stands for small form factor pluggable, With the help of SFP you can extend the switching capability by connecting the fiber/copper cable between two devices. SFP is the way of technology to connect the devices. You can use as a Single fiber, Dual Fiber, DWDM, WDM. It can support maximum of 150 Km. SFP is based on IEEE802.3 and SFF-8472. SFP transceivers are designed to support Continue reading

Basics of Multicast Addresses ( to

Today I am going to talk about basics of Multicast from the beginning. Before starting the concept of multicast you need to know about the unicast and the broadcast type of networks.

Unicast: Unicast is the traffic from from the single user to the single destination.
Broadcast: Broadcast is the traffic flow from the single user to everyone in the network.
Multicast: Multicast is the traffic flow from the single user to the specific group of the destinations in the network.

Fig 1.1- Multicast Vs Unicast

IP Multicast
IP multicast works as follows :
  • Multicast groups are identified by IP addresses in the range - (class D address) 
  • Every host (more precisely: interface) can join and leave a multicast group dynamically : no access control 
  • Every IP datagram sent to a multicast group is transmitted to all members of the group
  • IP multicast service is unreachable
  • IP multicast only supports UDP as higher Layer which means there is no multicast TCP.
  • All D class addresses are Multicast addresses. The addresses range are shown above from to
  • These addresses are dynamically Continue reading

DNS- Domain Name Server

Today I am going to talk about the DNS server. I knew some of the you already knew about the DNS. DNS stands for Domain Name Server and is a service to translate hostname into IP address. DNS is a distributed database implemented in a hierarchy of name servers and DNS is an application level protocol for message exchange between clients and servers.

Now question is Why we required DNS service ?
  • It is easier to remember a host name than it is to remember an IP address. 
  • A name has more meaning to a user than a 4 byte number. 
  • Applications such as FTP, HTTP, email, etc., all require the user to input a destination 
  • The user generally enters a host name 
  • The application takes the host name supplied by the user and forwards it to DNS for translation to an IP address 
Fig 1.1- DNS 

How DNS- Domain Name Server Works ?

  • DNS works by exchanging messages between client and server machines. 
  • A client application will pass the destination host name to the DNS process (in Unix referred to as the get host by name() routine to get the IP address. 
  • The application then sits Continue reading

DHCP Message Types

Today I am going to talk about the DHCP message types and the meaning of all the requests sent by server and client in DHCP process. The messages are shown below

Messages Types
Fig 1.1- Sample DHCP request
Fig1.2 - Sample DHCP Response

DHCPDISCOVER: Broadcast by a client to find available DHCP servers. 

DHCPOFFER: Response from a server to a DHCPDISCOVER and offering IP address and other parameters. 

DHCPREQUEST: Message from a client to servers that does one of the following: 
  • Requests the parameters offered by one of the servers and declines all other offers. 
  • Verifies a previously allocated address after a system or network change (a reboot for example). 
  • Requests the extension of a lease on a particular address. 
DHCPACK: Acknowledgement from server to client with parameters, including IP address. 

DHCPNACK: Negative acknowledgement from server to client, indicating that the client's lease has expired or that a requested IP address is incorrect. 

DHCPDECLINE: Message from client to server indicating that the offered address is already in use. 

DHCPRELEASE: Message from client to server canceling Continue reading
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