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1. Local Scope Multicast Addresses Multicast addresses that begin with FF02::/16 have a link-local scope i.e., routers will not forward these packets outside the local subnet. Multicast addresses that begin with FF08::/16 have an organizational-local scope i.e., packets sent to these addresses are forwarded throughout the enterprise but not out the internet. Command to verify the Local-scope Multicast addresses is show ipv6 interface G0/0 Key IPv6 Local-scope Multicast Addresses Multicast address Used to send data to IPv4 equivalent FF02::1 All nodes (All IPv6 interfaces that are on the link) A subnet broadcast address FF02::2 All routers (All IPv6 router interfaces on the link) None FF02::5 All OSPFv6 routers 224.0.0.5 FF02::6 All OSPFv6-Designated Routers 224.0.0.6 FF02::9 All RIPng routers 224.0.0.9 FF02::A All EIGRPv6 routers 224.0.0.10 FF02::1:2 All DHCPv6 Relay Agent Routers None 2. Solicied-Node Multicast Addresses It is also a Link-local multicas

Each IPv6 host including routers uses an additional unicast address called a Link-local address. Link-Local addresses are used for some overhead protocols that stay local to one subnet but not for transferring data.                                                                                                          eg., NDP (Neigbour Discovery protocol) which is the same as IPv4's ARP. Also, Routers use link-local addresses as the next-hop IP address in IPv6 routes. IPv6 hosts use Link-local addresses of the router(in the same subnet) as the default gateway address. Link-local addresses are unicast addresses, not multicast. Routers do not route packets with the link-local destination address. Every IPv6 host interface (and router interface) can create its own link-local address automatically, solving some initialization problems in hosts.  How Routers create Link-local addresses? IOS can create automatically or it can be configured using the command - IPv6

Static unicast address configuration There are 2 ways to configure the static address on routers, Configure the full 128-bit address using the ipv6 address interface subcommand.                        eg., ipv6 address 2001:DB6:1111:2::1/64                                                                                          Only configure the 64-bit prefix and let the router derive the second half of the address (Interface ID) using modified EUI-64. How to generate a unique interface ID using Modified EUI-64? EUI - Extended Unique Identifier 64 Bits 24 Bits 16 Bits 24 Bits Subnet Prefix Ist Half of MAC FFFE 2nd Half of MAC Invert the 7th Bit Example: Step 1: MAC address of the Interface - 1523.6131.7568 Step 2: Divide the MAC into two half parts              152361                             317568 Step 3: Insert FFFE in the middle              152361        FFFE            317568 Step 4: Write in the IPv6 format             1523:61FF: FE31:756

Global Unicast Address Works like Public IPv4 addresses. Should be registered with numbering authority. Assigned as a Global routing prefix by ISP. Can be used to connect to the internet. Globally unique.   Unique Local Unicast Address Works like Private IPv4 addresses. No need to register with numbering authority. Unable to connect to the internet directly. Same addresses can be used in multiple organizations. Unique Local Unicast Address Format 8 Bits 40 Bits 16 Bits 64 Bits FD Global ID (Pseudo-random) Subnet Interface ID Global routing prefix: Reserved block of IPv6 addresses, that only one company can use. Address Type First Hex Digits Global Unicast 2 or 3(originally); all not otherwise reserved. Unique Local FD Multicast FF Link-Local FE80 IPv6 subnet ID is also called as Subnet-router anycast address. Host IPv6 addresses can be configured statically and

To enter Global configuration command           config t Change/rename router name            R1# config t            R1(config)#hostname MST Enable Password           MST(config)# enable password cisco Configure Telnet Password           MST(config)#line vty 04           MST(config-line)# password cisco           MST(config-line)# login           MST(config-line)#exit Configure IP address          MST#config t          MST(config)#int fa 0/0          MST(config-if)#ip address 10.0.0.100  255.255.255.0          MST(config-if)#no shut          MST(config-if)# Configure Password Encryption         MST#config t         MST(config)#service password-encryption         MST(config)# do show run User Creation      MST(config)#username admin privilege 15 password cisco (15 - Full access) To check the password encryption           MST(config)#do sh run l in pass

Boot Sequences of the Operating System When we press the power button, If there is proper voltage, a short is created and send a pulse command to PSU (Power supply unit) to give power to all the devices and to send reset signals to the processor(CPU).                                                                                                                                                                                           CPU has the instruction pointer pointing to the reset vector within the system ROM and the CPU starts executing the small firmware or Jump instruction to load the BIOS.                                                                                    BIOS  initialize the primary graphics through video BIOS code and also the other secondary devices. BIOS starts the POST (Power ON Self Test) process which will  run the basic test for the devices and sets the device to it's default values. If there is any error during POST, beep codes and light co

Network Connection Type Speed Analog PO+A2:A29TS Modem      300 bps-56.7 kbps ITU V.21                                                       300 bps ITU V.22                                                          1.2 kbps ITU V.22bis                                          2.4 kbps ITU V.29/V.32                                         9.6 kbps Facsimile (Fax)                                      9.6 - 14.4 kbps Cellular Digital Packet Data CDPD      9.6 - 14.4 kbps ITU V.32bis                                                    14.4 kbps HSCSD                                                         28.8 - 56.0 kbps ITU V.90                                                       56.0 kbps T-0/E-0/J-0/DS-0 (1 Voice Channel)             64 kbps N-ISDN (Narrowband)                               

CSV File Format What is a CSV file? CSV file is a plain text file which uses commas as a column or field delimiter.  In 1972, the IBM Fortran first supported CSV files. What is a CSV file used for? CSV files are mainly used to transfer (import/export) large quantities of tabular data between different applications easily. To transfer data between databases, quite often CSV to SQL. As a CSV file is a plain text file, they are compatible with all the platforms avoiding incompatibilities such as word size or byte-order. As CSV files are plain text files, they are easy for the website developers to create. The CSV files are largely human-readable. How do I open a CSV file? A CSV file can be opened by the below programs, Microsoft Excel Just double click the CSV file, it will be opened in Microsoft Excel, if installed in the computer. If it asks to select the program in which you want to open, by “Open with” prompt, select Microsoft Excel. The