Ethernet - Revision history

Pbug: /* Wireless LAN */

2013-08-07T18:13:30Z

Wireless LAN

← Older revision		Revision as of 11:13, 7 August 2013
Line 49:		Line 49:
	=== Wireless LAN ===		=== Wireless LAN ===

	WLAN also called Wifi was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[ipsec]] to ensure additional security.		[[WLAN]] also called [[Wifi]] was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[ipsec]] to ensure additional security.

	[[Image:open-wifi-symbol.jpg]]		[[Image:open-wifi-symbol.jpg]]

Pbug: /* PPPoE */ typo

2009-08-09T14:23:41Z

PPPoE: typo

← Older revision		Revision as of 07:23, 9 August 2009
Line 55:		Line 55:
	=== PPPoE ===		=== PPPoE ===

	[[PPP]] over Ethernet is a hack of protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516 and involves packet ~~encasulation~~, a packet within a packet. As a result a PPPoE user will often have to dumb down their [[MTU]] and/or [[MRU]] settings. Although the default is usually 1500, this author has the following in his ppp.conf:		[[PPP]] over Ethernet is a hack of protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516 and involves packet encapsulation, a packet within a packet. As a result a PPPoE user will often have to dumb down their [[MTU]] and/or [[MRU]] settings. Although the default is usually 1500, this author has the following in his ppp.conf:
	set mru 1492		set mru 1492
	set mtu 1452		set mtu 1452
	as the best setting for his PPPoE sDSL connection.		as the best setting for his PPPoE sDSL connection.

Pbug: /* Wireless LAN */

2005-12-01T14:02:54Z

Wireless LAN

← Older revision		Revision as of 07:02, 1 December 2005
Line 50:		Line 50:

	WLAN also called Wifi was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[ipsec]] to ensure additional security.		WLAN also called Wifi was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[ipsec]] to ensure additional security.

			[[Image:open-wifi-symbol.jpg]]

	=== PPPoE ===		=== PPPoE ===

Pbug: /* Twisted Pair Copper Cabling */

2005-12-01T13:35:59Z

Twisted Pair Copper Cabling

← Older revision		Revision as of 06:35, 1 December 2005
Line 43:		Line 43:

	Ethernet copper cabling also called Twisted Pair cabling is composed of 4 pairs of copper wire which are twisted between the pairs and also twisted around in their plastic protective coating. The twist is to ensure shielding which is questionable. The ends of ethernet cabling are connectors called RJ-45 bits. The individual wires are colour coded and are visible in the RJ-45 connector from the top. The most common sequence is 1. green-white 2. green 3. orange-white 4. blue 5. blue-white 6. orange 7. brown-white 8. brown. This is the setup on both ends for what is called a straight-thru cable. The only wires actually used are positions 1, 2, 3 and 6. When you want to connect 2 ethernet cards directly without use of a [[hubs \| hub]] or [[switch]] you require a cable that is crossed-over or a cross-over cable. This is called so because positions 1 and 3 and 2 and 6 are crossed, so the end of the crossed end looks like this 1. orange-white 2. orange 3. green-white 4. blue 5. blue-white 6. green 7. brown-white 8. brown. The most common type of cabling for ethernet is category 5 cabling although there is category 5e now for gigabit. To attach the RJ-45 bits to the cabling a special tool called a RJ-45 crimper is used. Cheap version s are about $30 (CA) at cabling surplus stores.		Ethernet copper cabling also called Twisted Pair cabling is composed of 4 pairs of copper wire which are twisted between the pairs and also twisted around in their plastic protective coating. The twist is to ensure shielding which is questionable. The ends of ethernet cabling are connectors called RJ-45 bits. The individual wires are colour coded and are visible in the RJ-45 connector from the top. The most common sequence is 1. green-white 2. green 3. orange-white 4. blue 5. blue-white 6. orange 7. brown-white 8. brown. This is the setup on both ends for what is called a straight-thru cable. The only wires actually used are positions 1, 2, 3 and 6. When you want to connect 2 ethernet cards directly without use of a [[hubs \| hub]] or [[switch]] you require a cable that is crossed-over or a cross-over cable. This is called so because positions 1 and 3 and 2 and 6 are crossed, so the end of the crossed end looks like this 1. orange-white 2. orange 3. green-white 4. blue 5. blue-white 6. green 7. brown-white 8. brown. The most common type of cabling for ethernet is category 5 cabling although there is category 5e now for gigabit. To attach the RJ-45 bits to the cabling a special tool called a RJ-45 crimper is used. Cheap version s are about $30 (CA) at cabling surplus stores.

			[[Image:rj45-st.jpg]]
			[[Image:rj45-co.jpg]]

	=== Wireless LAN ===		=== Wireless LAN ===

Franks at 22:41, 29 November 2005

2005-11-29T22:41:18Z

← Older revision		Revision as of 15:41, 29 November 2005
Line 1:		Line 1:
	Ethernet is a method for communication also called CSMA/CD (carrier sense, media access / collision detect). It was developed at DEC first. It was cheaper than [[token ring]] for a Local Area Network ([[LAN]]) so it became the industrial standard. Ethernet has historically been used on copper cabling up to Gigabit speeds, but fibre-optic cabling is becoming very popular especially at Gigabit speeds. When ethernet is in a half-duplex setting (possibly connected to a [[hub]]) collisions can occur when two or more NICS broadcast at the same time. When a collission is detected a NIC will back off a random amount of time and try again, because the other cards also back off a random amount of time the odds are low that they will collide again. Today [[~~hub~~]]s are not used anymore but [[switch]]es which eliminate the need to put cards in [[half duplex]] mode.		Ethernet is a method for communication also called CSMA/CD (carrier sense, media access / collision detect). It was developed at DEC first. It was cheaper than [[token ring]] for a Local Area Network ([[LAN]]) so it became the industrial standard. Ethernet has historically been used on copper cabling up to Gigabit speeds, but fibre-optic cabling is becoming very popular especially at Gigabit speeds. When ethernet is in a half-duplex setting (possibly connected to a [[hubs\|hub]]) collisions can occur when two or more NICS broadcast at the same time. When a collission is detected a NIC will back off a random amount of time and try again, because the other cards also back off a random amount of time the odds are low that they will collide again. Today [[hubs]] are not used anymore but [[switch]]es which eliminate the need to put cards in [[half duplex]] mode.
	If you only have one network card,		If you only have one network card,
	# /sbin/ifconfig -a \| grep media		# /sbin/ifconfig -a \| grep media
Line 42:		Line 42:
	=== Twisted Pair Copper Cabling ===		=== Twisted Pair Copper Cabling ===

	Ethernet copper cabling also called Twisted Pair cabling is composed of 4 pairs of copper wire which are twisted between the pairs and also twisted around in their plastic protective coating. The twist is to ensure shielding which is questionable. The ends of ethernet cabling are connectors called RJ-45 bits. The individual wires are colour coded and are visible in the RJ-45 connector from the top. The most common sequence is 1. green-white 2. green 3. orange-white 4. blue 5. blue-white 6. orange 7. brown-white 8. brown. This is the setup on both ends for what is called a straight-thru cable. The only wires actually used are positions 1, 2, 3 and 6. When you want to connect 2 ethernet cards directly without use of a [[hub]] or [[switch]] you require a cable that is crossed-over or a cross-over cable. This is called so because positions 1 and 3 and 2 and 6 are crossed, so the end of the crossed end looks like this 1. orange-white 2. orange 3. green-white 4. blue 5. blue-white 6. green 7. brown-white 8. brown. The most common type of cabling for ethernet is category 5 cabling although there is category 5e now for gigabit. To attach the RJ-45 bits to the cabling a special tool called a RJ-45 crimper is used. Cheap version s are about $30 (CA) at cabling surplus stores.		Ethernet copper cabling also called Twisted Pair cabling is composed of 4 pairs of copper wire which are twisted between the pairs and also twisted around in their plastic protective coating. The twist is to ensure shielding which is questionable. The ends of ethernet cabling are connectors called RJ-45 bits. The individual wires are colour coded and are visible in the RJ-45 connector from the top. The most common sequence is 1. green-white 2. green 3. orange-white 4. blue 5. blue-white 6. orange 7. brown-white 8. brown. This is the setup on both ends for what is called a straight-thru cable. The only wires actually used are positions 1, 2, 3 and 6. When you want to connect 2 ethernet cards directly without use of a [[hubs \| hub]] or [[switch]] you require a cable that is crossed-over or a cross-over cable. This is called so because positions 1 and 3 and 2 and 6 are crossed, so the end of the crossed end looks like this 1. orange-white 2. orange 3. green-white 4. blue 5. blue-white 6. green 7. brown-white 8. brown. The most common type of cabling for ethernet is category 5 cabling although there is category 5e now for gigabit. To attach the RJ-45 bits to the cabling a special tool called a RJ-45 crimper is used. Cheap version s are about $30 (CA) at cabling surplus stores.

	=== Wireless LAN ===		=== Wireless LAN ===

Frankk: /* Wireless LAN */

2005-10-30T18:02:30Z

Wireless LAN

← Older revision		Revision as of 11:02, 30 October 2005
Line 46:		Line 46:
	=== Wireless LAN ===		=== Wireless LAN ===

	WLAN also called Wifi was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[~~IPsec~~]] to ensure additional security.		WLAN also called Wifi was first developed at Lucent with their Wavelan product. It is a standard based around IEEE 802.11b and g. At first Wifi could speak only 11 Mbps maximum which was then upgraded to 54 Mbps with the 802.11g standard. Wifi came with built-in encryption at first called WEP but the implementation of this [[cryptography]] was breakable. It should be noted that all Wifi should be encrypted with [[ipsec]] to ensure additional security.


	=== PPPoE ===		=== PPPoE ===

Frankk at 09:03, 28 October 2005

2005-10-28T09:03:45Z

← Older revision		Revision as of 02:03, 28 October 2005
Line 5:		Line 5:
	should show you what your network card is currently running at. If you have multiple cards, or are not getting the anticipated response, just try		should show you what your network card is currently running at. If you have multiple cards, or are not getting the anticipated response, just try
	# /sbin/ifconfig -a		# /sbin/ifconfig -a

			On [[BSD]], once you've determined your network device you can see what options it has in section 4 of the [[Manual]]. In this case I'm using sis0:
			man 4 sis


	=== Thinnet & Thicknet ===		=== Thinnet & Thicknet ===

Sysadmin: /* PPPoE */

2005-10-24T19:59:40Z

PPPoE

← Older revision		Revision as of 12:59, 24 October 2005
Line 47:		Line 47:
	=== PPPoE ===		=== PPPoE ===

	[[PPP]] over Ethernet is a hack of protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516 and involves packet encasulation, a packet within a packet. As a result a PPPoE user will often have to dumb down their MTU settings.		[[PPP]] over Ethernet is a hack of protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516 and involves packet encasulation, a packet within a packet. As a result a PPPoE user will often have to dumb down their [[MTU]] and/or [[MRU]] settings. Although the default is usually 1500, this author has the following in his ppp.conf:
			set mru 1492
			set mtu 1452
			as the best setting for his PPPoE sDSL connection.

Sysadmin: /* PPPoE */

2005-10-24T19:56:19Z

PPPoE

← Older revision		Revision as of 12:56, 24 October 2005
Line 47:		Line 47:
	=== PPPoE ===		=== PPPoE ===

	[[PPP]] over Ethernet is a protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516.		[[PPP]] over Ethernet is a hack of protocol spoken with most DSL home end-user connections. It is covered in [[RFC]] 2516 and involves packet encasulation, a packet within a packet. As a result a PPPoE user will often have to dumb down their MTU settings.

Sysadmin at 19:55, 24 October 2005

2005-10-24T19:55:13Z

← Older revision		Revision as of 12:55, 24 October 2005
Line 1:		Line 1:
	Ethernet is a method for communication also called CSMA/CD (carrier sense, media access / collision detect). It was developed at DEC first. It was cheaper than [[token ring]] for a Local Area Network ([[LAN]]) so it became the industrial standard. Ethernet has historically been used on copper cabling up to Gigabit speeds, but fibre-optic cabling is becoming very popular especially at Gigabit speeds. When ethernet is in a half-duplex setting (possibly connected to a [[hub]]) collisions can occur when two or more NICS broadcast at the same time. When a collission is detected a NIC will back off a random amount of time and try again, because the other cards also back off a random amount of time the odds are low that they will collide again. Today [[hub]]s are not used anymore but [[switch]]es which eliminate the need to put cards in [[half duplex]] mode.		Ethernet is a method for communication also called CSMA/CD (carrier sense, media access / collision detect). It was developed at DEC first. It was cheaper than [[token ring]] for a Local Area Network ([[LAN]]) so it became the industrial standard. Ethernet has historically been used on copper cabling up to Gigabit speeds, but fibre-optic cabling is becoming very popular especially at Gigabit speeds. When ethernet is in a half-duplex setting (possibly connected to a [[hub]]) collisions can occur when two or more NICS broadcast at the same time. When a collission is detected a NIC will back off a random amount of time and try again, because the other cards also back off a random amount of time the odds are low that they will collide again. Today [[hub]]s are not used anymore but [[switch]]es which eliminate the need to put cards in [[half duplex]] mode.
			If you only have one network card,
			# /sbin/ifconfig -a \| grep media
			media: Ethernet autoselect (100baseTX <full-duplex>)
			should show you what your network card is currently running at. If you have multiple cards, or are not getting the anticipated response, just try
			# /sbin/ifconfig -a

	=== Thinnet & Thicknet ===		=== Thinnet & Thicknet ===