Redes e Internet - UNSJ

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Redes e Internet

Informática Médica

Juan Pablo Graffigna

Temas

� Internet

� Capas de Red

� Topologías y estándares de capa física.

� Ethernet

� TCP/IP

� Algunos Servicios:

� DHCP, HTML, POP, SMTP, FTP

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Internet

� Red informática mundial, descentralizada, formada por la conexión directa entre computadoras u ordenadores mediante un protocolo especial de comunicación.

� Números

Internet - Usuarios

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Internet - Usuarios

Internet - Usuarios

Latinoamérica a crecido en 10 años 1032,8%

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Internet – Aspectos Generales

� WAN y LAN

� Accesos

Redes

� LAN: Una red de área local, red local o LAN (del inglés local area network) es la interconexión de varias computadoras y periféricos. Su extensión está limitada físicamente a un edificio o a un entorno de 200 metros, o con repetidores podría llegar a la distancia de un campo de 1 kilómetro.

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Capas de Red

Capas de Red

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Topologías

Ethernet

� Es una arquitectura para LAN desarrollada originalmente por Xerox Corporation en cooperación con DEC e Intel en 1976.

� Ethernet usa una topología de bus o estrella, y soporta en su versión original 10 Mbps.

� Esta especificación sirvió de base para el estándar IEEE 802.3, el cual especifica la capa física y las capas de software de bajo nivel.

� Ethernet utiliza el método CSMA/CD para manejar demandas simultáneas. Es el estándar de LAN más difundido actualmente.

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Ethernet

Ethernet at 10 billion bits per second over optical fiber. Multimode fiber supports distances

up to 300 meters; single mode fiber supports distances up to 40 kilometers.10Gigabit Ethernet

10 Mbps baseband Ethernet over three channels of a cable television system with a

maximum cable length of 3,600 meters.10Broad-36

10 Mbps baseband Ethernet over twisted pair cables with a maximum length of 100 meters.10Base-T

10 Mbps baseband Ethernet over two optical fibers using a passive hub to connect

communication devices.10Base-FP

10 Mbps baseband Ethernet over two optical fibers and can include an optional

asynchronous hub.10Base-FL

10 Mbps baseband Ethernet over two multi-mode optical fibers using a synchronous active

hub.10Base-FB

10 Mbps baseband Ethernet over optical fiber.10Base-F

10 Mbps baseband Ethernet over multi-channel coaxial cable with a maximum distance of

3,600 meters.10Base-36

10 Mbps baseband Ethernet over coaxial cable with a maximum distance of 500 meters.

Also referred to as Thick Ethernet or Thicknet or Thickwire.10Base-5

10 Mbps baseband Ethernet over coaxial cable with a maximum distance of 185 meters.

Also referred to as Thin Ethernet or Thinnet or Thinwire.10Base-2

DescriptionDesignation

Ethernet

A generic name for 1000 Mbps Ethernet systems.1000Base-X

1000 Mbps baseband Ethernet over four pairs of Category 5 unshielded twisted pair

cable.1000Base-T

1000 Mbps baseband Ethernet over two multimode optical fibers using shortwave laser

optics.1000Base-SX

1000 Mbps baseband Ethernet over two multimode or single-mode optical fibers using

longwave laser optics.1000Base-LX

1000 Mbps baseband Ethernet over two pairs of 150 shielded twisted pair cable.1000Base-CX

A generic name for 100 Mbps Ethernet systems.100Base-X

100 Mbps baseband Ethernet over two pairs of shielded twisted pair or Category 4

twisted pair cable.100Base-TX

100 Mbps baseband Ethernet over four pairs of Category 3 or higher unshielded

twisted pair cable.100Base-T4

100 Mbps baseband Ethernet over two pairs of Category 3 or higher unshielded

twisted pair cable.100Base-T2

100 Mbps baseband Ethernet over twisted pair cable.100Base-T

100 Mbps baseband Ethernet over two multimode optical fibers.100Base-FX

DescriptionDesignation

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Ethernet

Ethernet

� Frame 1 (62 bytes on wire, 62 bytes captured)Arrival Time: Mar 21, 2004 20:02:28.850908000 Time delta from previous packet: 0.000000000 secondsTime since reference or first frame: 0.000000000 secondsFrame Number: 1 Packet Length: 62 bytesCapture Length: 62 bytes

Ethernet II, Src: 00:e0:4c:ec:bf:db, Dst: 00:a0:c9:49:c2:00Destination: 00:a0:c9:49:c2:00 (192.168.0.10) Source: 00:e0:4c:ec:bf:db (RealtekS_ec:bf:db) Type: IP (0x0800)

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TCP/IP

� Es la abreviatura de Transmission Control Protocol / Internet protocol.

� Es un conjunto de protocolos de comunicación utilizados para conectar computadoras a internet. TCP / IP usa varios protocolos, los dos principales son TCP e IP. TCP / IP está integrado en el sistema operativo UNIX y es usado por Internet, por lo que es el estándar de facto para la transmisión de datos a través de las redes. Incluso los sistemas operativos de red que tienen sus propios protocolos, como Netware, también admiten TCP / IP.

TCP/IP

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TCP/IP

IP

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IP� Internet Protocol, Src Addr: 192.168.0.160 (192.168.0.160), Dst Addr: 192.

168.0.10 (192.168.0.10)Version: 4 Header length: 20 bytesDifferentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)

0000 00.. = Differentiated Services Codepoint: Default (0x00) .... ..0. = ECN-Capable Transport (ECT): 0 .... ...0 = ECN-CE: 0

Total Length: 48 Identification: 0x02a4 (676) Flags: 0x04

0... = Reserved bit: Not set.1.. = Don't fragment: Set..0. = More fragments: Not set

Fragment offset: 0 Time to live: 128 Protocol: TCP (0x06) Header checksum: 0x7629 (correct) Source: 192.168.0.160 (192.168.0.160) Destination: 192.168.0.10 (192.168.0.10)

TCP

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TCP

Transmission Control Protocol, Src Port: 1046 (1046), Dst Port: 22 (22), Seq: 0, Ack: 0, Len: 0Source port: 1046 (1046) Destination port: 22 (22) Sequence number: 0 Header length: 28 bytesFlags: 0x0002 (SYN)

0... .... = Congestion Window Reduced (CWR): Not set.0.. .... = ECN-Echo: Not set..0. .... = Urgent: Not set...0 .... = Acknowledgment: Not set.... 0... = Push: Not set.... .0.. = Reset: Not set.... ..1. = Syn: Set.... ...0 = Fin: Not set

Window size: 64240 Checksum: 0x4cb5 (correct) Options: (8 bytes)

Maximum segment size: 1460 bytesNOPNOPSACK permitted

Servicios

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TCP-UDP

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