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Oracle Date Functions
ions This page provides you with the most commonly used Oracle date functions that help you handle date and time data easily and more effectively. Function Example Result Description ADD_MONTHS <span>ADD_MONTHS( DATE '2016-02-29', 1 ) 31-MAR-16 Add a number of months (n) to a date and return the same day which is n of months away. CURRENT_DATE SELECT CURRENT_DATE FROM dual 06-AUG-2017 19:43:44 Return the current date

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### A) Oracle NVL2() function with numeric data type example

The following statement returns two because the first argument is null.

 1 2 3 4 SELECT NVL2 ( NULL , 1, 2) -- 2 FROM dual;

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Oracle NVL2 Function By Practical Examples
he following flowchart illustrates how the Oracle NVL2() function works. Oracle NVL2() function examples Let’s take some examples of using the Oracle NVL2() function to understand how it works. <span>A) Oracle NVL2() function with numeric data type example The following statement returns two because the first argument is null. 1 2 3 4 SELECT NVL2(NULL, 1, 2) -- 2 FROM dual; B) Oracle NVL2() function with character data type example The following example returns the second argument which is the ABC string because the first argument is not null. 1 2 3 4 SELE

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### B) Oracle NVL2() function with character data type example

The following example returns the second argument which is the ABC string because the first argument is not null.

 1 2 3 4 SELECT NVL2 (1, 'ABC' , 'XYZ' ) FROM dual;

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Oracle NVL2 Function By Practical Examples
nd how it works. A) Oracle NVL2() function with numeric data type example The following statement returns two because the first argument is null. 1 2 3 4 SELECT NVL2(NULL, 1, 2) -- 2 FROM dual; <span>B) Oracle NVL2() function with character data type example The following example returns the second argument which is the ABC string because the first argument is not null. 1 2 3 4 SELECT NVL2(1, 'ABC', 'XYZ') FROM dual; C) Oracle NVL2() function with orders example See the following employees and orders tables from the sample database : The following query retrieves order id, order date, and the name o

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Oracle NVL2() function and CASE expression

The NVL2() function is logically equivalent to the following CASE expression:

 CASE WHEN e1 IS NOT NULL THEN e2 ELSE e3 END

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Oracle NVL2 Function By Practical Examples
ction to implement a logic that if the commission IS NOT NULL, then the total compensations is just salary. In case the commission IS NULL, calculate the full payment as salary plus commission. <span>Oracle NVL2() function and CASE expression The NVL2() function is logically equivalent to the following CASE expression: 1 2 3 4 5 6 CASE WHEN e1 IS NOT NULL THEN e2 ELSE e3 END As you can see, the NVL2() function is more concise and less verbose. In this tutorial, you have learned how to use the Oracle NVL2() function to substitute a null value with different

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The following statement returns the orders placed by customers between December 1, 2016, and December 31, 2016:

 SELECT order_id, customer_id, status, order_date FROM orders WHERE order_date BETWEEN DATE '2016-12-01' AND DATE '2016-12-31' ORDER BY order_date;

Here is the result:

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Oracle BETWEEN: Select Rows Whose Values are in a Range
ost NOT BETWEEN 500 AND 600 ORDER BY product_name; The following illustrates the result: B) Oracle BETWEEN dates example Let’s use the orders table in the sample database for the demonstration: <span>The following statement returns the orders placed by customers between December 1, 2016, and December 31, 2016: 1 2 3 4 5 6 7 8 9 10 11 SELECT order_id, customer_id, status, order_date FROM orders WHERE order_date BETWEEN DATE '2016-12-01' AND DATE '2016-12-31' ORDER BY order_date; Here is the result: In this tutorial, you have learned how to use the Oracle BETWEEN operator to select rows that are in a specific range. Was this tutorial helpful? yesno Previous Tutorial: Oracle IN Next

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To query products whose standard costs are not between 500 and 600, you add the NOT operator to the above query as follows:

 SELECT product_name, standard_cost FROM products WHERE standard_cost NOT BETWEEN 500 AND 600 ORDER BY product_name;

The following illustrates the result:

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Oracle BETWEEN: Select Rows Whose Values are in a Range
In this example, we compared the values in the standard cost ( standard_cost) column with a range from 500 to 600. The query returned only products whose standard costs are between that range: <span>To query products whose standard costs are not between 500 and 600, you add the NOT operator to the above query as follows: 1 2 3 4 5 6 7 8 9 SELECT product_name, standard_cost FROM products WHERE standard_cost NOT BETWEEN 500 AND 600 ORDER BY product_name; The following illustrates the result: B) Oracle BETWEEN dates example Let’s use the orders table in the sample database for the demonstration: The following statement returns the orders placed by customers between December

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This example decodes the value warehouse_id. If warehouse_id is 1, then the function returns 'Southlake'; if warehouse_id is 2, then it returns 'San Francisco'; and so forth. If warehouse_id is not 1, 2, 3, or 4, then the function returns 'Non domestic'.

SELECT product_id,
DECODE (warehouse_id,
1, 'Southlake',
2, 'San Francisco',
3, 'New Jersey',
4, 'Seattle', 'Non domestic') "Location of inventory"
FROM inventories WHERE product_id < 1775;

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DECODE
al, "Floating-Point Numbers" for information on floating-point comparison semantics, and "Implicit and Explicit Data Conversion" for information on the drawbacks of implicit conversion Examples <span>This example decodes the value warehouse_id. If warehouse_id is 1, then the function returns 'Southlake'; if warehouse_id is 2, then it returns 'San Francisco'; and so forth. If warehouse_id is not 1, 2, 3, or 4, then the function returns 'Non domestic'. SELECT product_id, DECODE (warehouse_id, 1, 'Southlake', 2, 'San Francisco', 3, 'New Jersey', 4, 'Seattle', 'Non domestic') "Location of inventory" FROM inventories WHERE product_id < 1775; Scripting on this page enhances content navigation, but does not change the content in any way. <span>

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### A) Oracle GROUP BY basic example

The following statement uses the GROUP BY clause to find unique order statuses from the orders table:

 SELECT status FROM orders GROUP BY status;

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The Ultimate Guide to Oracle GROUP BY with Examples
c2,c3); Please check it out the ROLLUP tutorial for the more information. Oracle GROUP BY examples We will use the following orders and order_items in the sample database for the demonstration: <span>A) Oracle GROUP BY basic example The following statement uses the GROUP BY clause to find unique order statuses from the orders table: 1 2 3 4 5 6 SELECT status FROM orders GROUP BY status; This statement has the same effect as the following statement that uses the DISTINCT operator: 1 2 3 4 SELECT DISTINCT status FROM orders; B) Oracle GROUP BY with an aggregate function

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B) Oracle GROUP BY with an aggregate function example

The following statement returns the number of orders by customers:

 SELECT customer_id, COUNT ( order_id ) FROM orders GROUP BY customer_id ORDER BY customer_id;

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The Ultimate Guide to Oracle GROUP BY with Examples
1 2 3 4 5 6 SELECT status FROM orders GROUP BY status; This statement has the same effect as the following statement that uses the DISTINCT operator: 1 2 3 4 SELECT DISTINCT status FROM orders; <span>B) Oracle GROUP BY with an aggregate function example The following statement returns the number of orders by customers: 1 2 3 4 5 6 7 8 9 SELECT customer_id, COUNT( order_id ) FROM orders GROUP BY customer_id ORDER BY customer_id; In this example, we grouped the orders by customers and used the COUNT() function to return the number of orders per group. To get more meaningful data, you can join the orders table wi

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In this example, we grouped the orders by customers and used the COUNT() function to return the number of orders per group.

To get more meaningful data, you can join the orders table with the customers table as follows:

 SELECT name, COUNT ( order_id ) FROM orders INNER JOIN customers USING (customer_id) GROUP BY name ORDER BY name;

Here is the result:

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The Ultimate Guide to Oracle GROUP BY with Examples
unction example The following statement returns the number of orders by customers: 1 2 3 4 5 6 7 8 9 SELECT customer_id, COUNT( order_id ) FROM orders GROUP BY customer_id ORDER BY customer_id; <span>In this example, we grouped the orders by customers and used the COUNT() function to return the number of orders per group. To get more meaningful data, you can join the orders table with the customers table as follows: 1 2 3 4 5 6 7 8 9 10 11 SELECT name, COUNT( order_id ) FROM orders INNER JOIN customers USING(customer_id) GROUP BY name ORDER BY name; Here is the result: C) Oracle GROUP BY with an expression example The following example groups the orders by year and returns the number of orders per year. 1 2 3 4 5 6 7 8 9 SELECT EXTRACT(YEAR FROM order

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### C) Oracle GROUP BY with an expression example

The following example groups the orders by year and returns the number of orders per year.

 SELECT EXTRACT ( YEAR FROM order_date) YEAR , COUNT ( order_id ) FROM orders GROUP BY EXTRACT ( YEAR FROM order_date) ORDER BY YEAR ;

In this example, we used the EXTRACT() function to get the year information from the order’s dates.

Unlike the previous examples, we used an expression that returns the year in the GROUP BY clause.

The following picture illustrates the result:

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The Ultimate Guide to Oracle GROUP BY with Examples
with the customers table as follows: 1 2 3 4 5 6 7 8 9 10 11 SELECT name, COUNT( order_id ) FROM orders INNER JOIN customers USING(customer_id) GROUP BY name ORDER BY name; Here is the result: <span>C) Oracle GROUP BY with an expression example The following example groups the orders by year and returns the number of orders per year. 1 2 3 4 5 6 7 8 9 SELECT EXTRACT(YEAR FROM order_date) YEAR, COUNT( order_id ) FROM orders GROUP BY EXTRACT(YEAR FROM order_date) ORDER BY YEAR; In this example, we used the EXTRACT() function to get the year information from the order’s dates. Unlike the previous examples, we used an expression that returns the year in the GROUP BY clause. The following picture illustrates the result: D) Oracle GROUP BY with WHERE clause example This example uses the GROUP BY clause with a WHERE clause to return the number of shipped orders for every customer: 1 2 3 4 5 6 7 8 9 10 11

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### D) Oracle GROUP BY with WHERE clause example

This example uses the GROUP BY clause with a WHERE clause to return the number of shipped orders for every customer:

 SELECT name, COUNT ( order_id ) FROM orders INNER JOIN customers USING (customer_id) WHERE status = 'Shipped' GROUP BY name ORDER BY name;

Here is the output:

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The Ultimate Guide to Oracle GROUP BY with Examples
get the year information from the order’s dates. Unlike the previous examples, we used an expression that returns the year in the GROUP BY clause. The following picture illustrates the result: <span>D) Oracle GROUP BY with WHERE clause example This example uses the GROUP BY clause with a WHERE clause to return the number of shipped orders for every customer: 1 2 3 4 5 6 7 8 9 10 11 SELECT name, COUNT( order_id ) FROM orders INNER JOIN customers USING(customer_id) WHERE status = 'Shipped' GROUP BY name ORDER BY name; Here is the output: Note that the Oracle always evaluates the condition in the WHERE clause before the GROUP BY clause. E) Oracle GROUP BY with ROLLUP example The following statement computes the sales amo

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### E) Oracle GROUP BY with ROLLUP example

The following statement computes the sales amount and groups them by customer_id, status, and (customer_id, status):

 1 2 3 4 5 6 7 8 9 10 11 12 13 SELECT customer_id, status, SUM ( quantity * unit_price ) sales FROM orders INNER JOIN order_items USING (order_id) GROUP BY ROLLUP( customer_id, status );

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The Ultimate Guide to Oracle GROUP BY with Examples
USING(customer_id) WHERE status = 'Shipped' GROUP BY name ORDER BY name; Here is the output: Note that the Oracle always evaluates the condition in the WHERE clause before the GROUP BY clause. <span>E) Oracle GROUP BY with ROLLUP example The following statement computes the sales amount and groups them by customer_id, status, and (customer_id, status): 1 2 3 4 5 6 7 8 9 10 11 12 13 SELECT customer_id, status, SUM( quantity * unit_price ) sales FROM orders INNER JOIN order_items USING(order_id) GROUP BY ROLLUP( customer_id, status ); In this tutorial, you have learned how to use the Oracle GROUP BY clause to group rows into groups. Was this tutorial helpful? yesno Previous Tutorial: Oracle Self Join Next Tutorial: O

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What is the behind the ARP protocol ?

* find out the hardware (MAC) address of a device from an IP address

* used when a device wants to communicate with some other device on a local network (for example on an Ethernet network)

* sending device uses ARP to translate IP addresses to MAC addresses. The device sends an ARP request message containing the IP address of the receiving device.

* All devices on a local network segment see the message, but only the device that has that IP address responds with the ARP reply message containing its MAC address. The sending device now has enough information to send the packet to the receiving device.

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nly the device that has that IP address responds with the ARP reply message containing its MAC address. The sending device now has enough information to send the packet to the receiving device. <span>ARP request packets are sent to the broadcast addresses (FF:FF:FF:FF:FF:FF for the Ethernet broadcasts and 255.255.255.255 for the IP broadcast). Here is the explanation otf the ARP process: [imagelink] Let’s say that Host A wants to communicate with host B. Host A knows the IP address of host B, but it doesn’t know the host B’s

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How does the ARP protocol process works ?

Here is the explanation otf the ARP process:

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#### Flashcard 4295374802188

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Multicast frames have a value of 1 in the least-significant bit of the first octet of the destination address

* Ethernet multicast address would be 01:00:0C:CC:CC:CC (used by CDPCisco Discovery Protocol).

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#### Flashcard 4295379782924

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IPv4: Version field ?

- Definition

- #Bits

Here is a description of each field:

• Version – the version of the IP protocol.
• For IPv4: Eselsbrücke (Vier)ersion := 4.

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ader is a prefix to an IP packet that contains information about the IP version, length of the packet, source and destination IP addresses, etc. It consists of the following fields: [imagelink] <span>Here is a description of each field: Version – the version of the IP protocol. For IPv4, this field has a value of 4. Header length – the length of the header in 32-bit words. The minumum value is 20 bytes, and the maximum value is 60 bytes. Priority and Type of Service – specifies how the datagram sho

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- Definition

- Word (min., max.) ?

* the length of the header in 32-bit words

* (min: 20 bytes, max. 60 bytes)

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ination IP addresses, etc. It consists of the following fields: [imagelink] Here is a description of each field: Version – the version of the IP protocol. For IPv4, this field has a value of 4. <span>Header length – the length of the header in 32-bit words. The minumum value is 20 bytes, and the maximum value is 60 bytes. Priority and Type of Service – specifies how the datagram should be handled. The first 3 bits are the priority bits. Total length – the length of the entire packet (header + data). The

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IPv4: Priority and Type of Service

- Definition

- first 3 Bits are ... ?

Priority and Type of Service – specifies how the datagram should be handled.

* first 3 bits are the priority bits.

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he version of the IP protocol. For IPv4, this field has a value of 4. Header length – the length of the header in 32-bit words. The minumum value is 20 bytes, and the maximum value is 60 bytes. <span>Priority and Type of Service – specifies how the datagram should be handled. The first 3 bits are the priority bits. Total length – the length of the entire packet (header + data). The minimum length is 20 bytes, and the maximum is 65,535 bytes. Identification – used to differentiate fragmented packet

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IPv4: Total Length

- Definition

- min, max. Length

Total length – the length of the entire packet (header + data).

* min. length is 20 bytes

* max. is 65,535 bytes

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bit words. The minumum value is 20 bytes, and the maximum value is 60 bytes. Priority and Type of Service – specifies how the datagram should be handled. The first 3 bits are the priority bits. <span>Total length – the length of the entire packet (header + data). The minimum length is 20 bytes, and the maximum is 65,535 bytes. Identification – used to differentiate fragmented packets from different datagrams. Flags – used to control or identify fragments. Fragmented offset – used for fragmentation and reassem

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IPv4: Identification - Definition ?
Identification – used to differentiate fragmented packets from different datagrams.

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agram should be handled. The first 3 bits are the priority bits. Total length – the length of the entire packet (header + data). The minimum length is 20 bytes, and the maximum is 65,535 bytes. <span>Identification – used to differentiate fragmented packets from different datagrams. Flags – used to control or identify fragments. Fragmented offset – used for fragmentation and reassembly if the packet is too large to put in a frame. Time to live – limits a datagram’s

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IPv4: Flags- Definitions ?

Flags – used to control or identify fragments.

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length of the entire packet (header + data). The minimum length is 20 bytes, and the maximum is 65,535 bytes. Identification – used to differentiate fragmented packets from different datagrams. <span>Flags – used to control or identify fragments. Fragmented offset – used for fragmentation and reassembly if the packet is too large to put in a frame. Time to live – limits a datagram’s lifetime. If the packet doesn’t get to its des

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IPv4: Fragmented Offset - Definition ?
Fragmented offset – used for fragmentation and reassembly if the packet is too large to put in a frame.

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e minimum length is 20 bytes, and the maximum is 65,535 bytes. Identification – used to differentiate fragmented packets from different datagrams. Flags – used to control or identify fragments. <span>Fragmented offset – used for fragmentation and reassembly if the packet is too large to put in a frame. Time to live – limits a datagram’s lifetime. If the packet doesn’t get to its destination before the TTL expires, it is discarded. Protocol – defines the protocol used in the data porti

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IPv4 - Time to Live ?
Time to live – limits a datagram’s lifetime. If the packet doesn’t get to its destination before the TTL expires, it is discarded.

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agmented packets from different datagrams. Flags – used to control or identify fragments. Fragmented offset – used for fragmentation and reassembly if the packet is too large to put in a frame. <span>Time to live – limits a datagram’s lifetime. If the packet doesn’t get to its destination before the TTL expires, it is discarded. Protocol – defines the protocol used in the data portion of the IP datagram. For example, TCP is represented by the number 6 and UDP by 17. Header checksum – used for error-checking of

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IPv4: Protocol - Definition ?
Protocol – defines the protocol used in the data portion of the IP datagram. For example, TCP is represented by the number 6 and UDP by 17.

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n and reassembly if the packet is too large to put in a frame. Time to live – limits a datagram’s lifetime. If the packet doesn’t get to its destination before the TTL expires, it is discarded. <span>Protocol – defines the protocol used in the data portion of the IP datagram. For example, TCP is represented by the number 6 and UDP by 17. Header checksum – used for error-checking of the header. If a packet arrives at a router and the router calculates a different checksum than the one specified in this field, the packet

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* If a packet arrives at a router and the router calculates a different checksum than the one specified in this field, the packet will be discarded.

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destination before the TTL expires, it is discarded. Protocol – defines the protocol used in the data portion of the IP datagram. For example, TCP is represented by the number 6 and UDP by 17. <span>Header checksum – used for error-checking of the header. If a packet arrives at a router and the router calculates a different checksum than the one specified in this field, the packet will be discarded. Source IP address – the IP address of the host that sent the packet. Destination IP address – the IP address of the host that should receive the packet. Options – used for network testi

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Source IP address – the IP address of the host that sent the packet.

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cksum – used for error-checking of the header. If a packet arrives at a router and the router calculates a different checksum than the one specified in this field, the packet will be discarded. <span>Source IP address – the IP address of the host that sent the packet. Destination IP address – the IP address of the host that should receive the packet. Options – used for network testing, debugging, security, and more. This field is usually empty. Consi

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a router and the router calculates a different checksum than the one specified in this field, the packet will be discarded. Source IP address – the IP address of the host that sent the packet. <span>Destination IP address – the IP address of the host that should receive the packet. Options – used for network testing, debugging, security, and more. This field is usually empty. Consider the following IP header, captured with Wireshark: [imagelink] Notice the fields

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IPv4: Options ?
Options – used for network testing, debugging, security, and more. This field is usually empty.

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his field, the packet will be discarded. Source IP address – the IP address of the host that sent the packet. Destination IP address – the IP address of the host that should receive the packet. <span>Options – used for network testing, debugging, security, and more. This field is usually empty. Consider the following IP header, captured with Wireshark: [imagelink] Notice the fields in the header: the IP version is IPv4, the header length is 20 bytes, the upper-level protocol u

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The ARP table on a Cisco router September 7, 2018January 19, 2019 upravnik

Just like regular hosts, if a Cisco router wants to exchange frames with a host in the same subnet, it needs to know its MAC address. The IP-to-MAC address mapping are kept in the router’s ARP table. Consider the following example:

R1 has two connected subnets – 10.0.0.0/24 and 172.16.0.0./16. Before exchanging frames with either host, R1 will need to know their MAC addresses. Here is the output of the R1’s ARP table:

R1#show ip arp

Internet  10.0.0.1                -   0060.5C32.7E01  ARPA   GigabitEthernet0/0
Internet  10.0.0.10               6   000C.85CA.AD73  ARPA   GigabitEthernet0/0
Internet  172.16.0.1              -   0060.5C32.7E02  ARPA   GigabitEthernet0/1
Internet  172.16.0.2              10  0001.63DB.1802  ARPA   GigabitEthernet0/1

The ARP table contains two entries for R1’s own two interfaces with the IP address of 10.0.0.1 and 172.16.0.1. The – in the age column indicates that the entry will never be timed out.

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The ARP table on a Cisco router
The ARP table on a Cisco router Skip to content [emptylink] Search for: Menu Home What is CCNA? Buy the ebook The ARP table on a Cisco router September 7, 2018January 19, 2019 upravnik Just like regular hosts, if a Cisco router wants to exchange frames with a host in the same subnet, it needs to know its MAC address. The IP-to-MAC address mapping are kept in the router’s ARP table. Consider the following example: [imagelink] R1 has two connected subnets – 10.0.0.0/24 and 172.16.0.0./16. Before exchanging frames with either host, R1 will need to know their MAC addresses. Here is the output of the

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Here are the steps R1 needs to take before forwarding frames to Host A:

1. R1 wants to communicate with Host A. R1 checks its routing table. The subnet on which Host A resides is a directly connected subnet.
2. R1 checks its ARP table to find out whether the Host A’s MAC address is known. If it is not, R1 will send an ARP request to the broadcast MAC address of FF:FF:FF:FF:FF:FF.
3. Host A receives the frame and sends its MAC address to R1 (ARP reply). The host also updates its own ARP table with the MAC address of the Gigabit0/0 interface on R1.
5. Since both hosts now know each other MAC addresses, the communication can occur.

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The ARP table on a Cisco router

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What does the show mac-address-table command ?

You can display the MAC address table of the switch by using the show mac-address-table command:

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Layer 2 switching
up in its MAC address table and forwards the frame only out Fa0/1 port, the port on which host B is connected. Other hosts on the network will not be involved in the communication: [imagelink] <span>You can display the MAC address table of the switch by using the show mac-address-table command: [imagelink] Jan 26, 2016upravnik Post navigation Differences between OSPF and EIGRP Collision & broadcast domain [imagelink] CONTENT #1 Networking basics What is a network? OSI &amp

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Explain the need for Data Link Layer Switching

Layer 2 switching (or Data Link layer switching)

* using devices’ MAC addresses on a LAN to segment a network. Switches and bridges are used for Layer 2 switching

* break up one large collision domain into multiple smaller ones.

* Switches have more ports than bridges, can inspect incoming traffic and make forwarding decisions accordingly

* Each port on a switch is a separate collision domain.

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Layer 2 switching

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How does a Switch works (simple Explanation) ?

### How switches work (1. Run) ?

* Each network card has a unique identifier called a Media Access Control (MAC) address.

* This address is used in LANs for communication between devices on the same network segment.

* Devices that want to communicate need to know each other MAC address before sending out packets.

* use a process called ARP (Address Resolution Protocol) to find out the MAC address of another device.

* When the hardware address of the destination host is known, the sending host has all the required information to communicate with the remote host.

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Explain the images of the ARP example !

Let’s say that host A wants to communicate with host B for the first time. Host A knows the IP address of host B, but since this is the first time the two hosts communicate, the hardware (MAC) addresses are not known.

1. ARP Request + ARP Reply

ARP Request + ARP Reply => IP-MAC mapping learnt => ?

ARP Request

* Host A uses the ARP process to find out the MAC address of host B.

* switch knows the MAC address of the host A because of the ARP request.

* The switch forwards the ARP request out all ports except the port the host A is connected to.

* Host B receives the ARP request and responds with its MAC address.

* Host B also learns the MAC address of host A (because host A sent its MAC address in the ARP request).

* The switch learns which MAC addresses are associated with which port.

* host B responded with the ARP reply that included its MAC address => switch knows the MAC address of host B => MAC address table got address

Learn IP-MAC mapping

* Now, when host A sends a packet to host B, the switch looks up in its MAC address table and forwards the frame only out Fa0/1 port, the port on which host B is connected.

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How does the 3-Way Handshake works ?

As the name implies, the three way handshake process consists of three steps:

1. Host A initiates the connection by sending the TCP SYN (random number 5432 marks sequence beginning ) packet to the destination host.
2. The Server receives the packet and responds with its own sequence number. The response also includes the ACK (Host A’s sequence number+ 1 = 5433).
3. Host A acknowledges the response of the Server by sending the ACK, which is the Server’s sequence number + 1.

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TCP three-way handshake
municate. TCP uses a process called three-way handshake to negotiate the sequence and acknowledgment fields and start the session. Here is a graphical representation of the process: [imagelink] <span>As the name implies, the three way handshake process consists of three steps: Host A initiates the connection by sending the TCP SYN packet to the destination host. The packet contains the random sequence number (e.g. 5432) which marks the beginning of the sequence numbers for data that the Host A will transmit. The Server receives the packet and responds with its own sequence number. The response also includes the acknowledgment number, which is Host A’s sequence number incremented by 1 (in our case, that would be 5433). Host A acknowledges the response of the Server by sending the acknowledgment number, which is the Server’s sequence number incremented by 1. Here is another picture with the numbers included: [imagelink] After the data transmission process is finished, TCP will terminate the connection between two endpoints. This four-step p

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How does the TCP connection terminate in a 4-Step process ?

After the data transmission process is finished, TCP will terminate the connection between two endpoints. This four-step process is illustrated below: