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CS615 - Aspects of System Administration Slide 1 CS615 - Aspects of System Administration Networking I Department of Computer Science Stevens Institute of Technology Jan Schaumann jschauma@stevens.edu https://stevens.netmeister.org/615/

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CS615 - Aspects of System Administration Slide 1

CS615 - Aspects of System Administration Networking I

Department of Computer Science Stevens Institute of Technology Jan Schaumann jschauma@stevens.edu https://stevens.netmeister.org/615/

Networking I February 24, 2020

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Networking I

Networking I February 24, 2020

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Team Missions

https://www.us-cert.gov/ics/advisories/icsa-19-274-01 https://is.gd/soixLV https://is.gd/vSuYvF https://is.gd/qkXhe2

Networking I February 24, 2020

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TCP

Networking I February 24, 2020

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Networking I

Networking I February 24, 2020

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Networking I

Networking I February 24, 2020

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Networking I

Networking I February 24, 2020

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Networking I

$ sudo tcpdump -w /tmp/out port 80 & $ curl -s -I http://www.cs.stevens.edu/ >/dev/null $ fg ^C $ sudo tcpdump -r /tmp/out -n -XX -c 1 15:23:43.477095 IP 172.16.1.30.51525 > 155.246.56.11.80: Flags [S], seq 1016422373, win 65535, options [mss 1460,nop,wscale 6,nop,nop,TS val 86305166 ecr 0,sackOK,eo 0x0000: c4b3 01db afe2 8c85 9047 b4f6 0800 4500 .........G....E. 0x0010: 0040 0000 4000 4006 b988 ac10 011e 9bf6 .@..@.@......... 0x0020: 380b c945 0050 3c95 5fe5 0000 0000 b002 8..E.P<._....... 0x0030: ffff 6109 0000 0204 05b4 0103 0306 0101 ..a............. 0x0040: 080a 0524 e98e 0000 0000 0402 0000 ...$..........

Networking I February 24, 2020

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Networking I

Networking I February 24, 2020

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Networking I

Layers: 0x0000: c4b3 01db afe2 8c85 9047 b4f6 0800 4500 .........G....E. 0x0010: 0040 0000 4000 4006 b988 ac10 011e 9bf6 .@..@.@......... 0x0020: 380b c945 0050 3c95 5fe5 0000 0000 b002 8..E.P<._....... 0x0030: ffff 6109 0000 0204 05b4 0103 0306 0101 ..a............. 0x0040: 080a 0524 e98e 0000 0000 0402 0000 ...$.......... Link layer information; here: Ethernet Network layer information; here: IP Transport layer information; here: TCP

Networking I February 24, 2020

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Networking I

OSI Layer 2 / TCP/IP Layer 1: Ethernet information: 0x0000: c4b3 01db afe2 8c85 9047 b4f6 0800 4500 .........G....E. 0x0010: 0040 0000 4000 4006 b988 ac10 011e 9bf6 .@..@.@......... 0x0020: 380b c945 0050 3c95 5fe5 0000 0000 b002 8..E.P<._....... 0x0030: ffff 6109 0000 0204 05b4 0103 0306 0101 ..a............. 0x0040: 080a 0524 e98e 0000 0000 0402 0000 ...$.......... Destination address: c4:b3:01:db:af:e2 Source address: 8c:85:90:47:b4:f6 Type: IP (0800) IPv4 stuff TCP stuff $ ifconfig en0 | grep ether ether 8c:85:90:47:b4:f6

Networking I February 24, 2020

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Networking I

OSI Layer 3 / TCP/IP Layer 2: Internet Protocol: 0x0000: c4b3 01db afe2 8c85 9047 b4f6 0800 4500 .........G....E. 0x0010: 0040 0000 4000 4006 b988 ac10 011e 9bf6 .@..@.@......... 0x0020: 380b c945 0050 3c95 5fe5 0000 0000 b002 8..E.P<._....... 0x0030: ffff 6109 0000 0204 05b4 0103 0306 0101 ..a............. 0x0040: 080a 0524 e98e 0000 0000 0402 0000 ...$.......... Version 4 (0100) + Header Length 20 (0101) = 01000101 = 45 DSCP default (000000) + Not-ECN (00) = 00 Total length = 0040 = 64 Identification = 0000 Flags = Don’t Fragment (010) + Frag Offset (00000) = 4000 TTL= 40 = 64

Networking I February 24, 2020

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Networking I

OSI Layer 3 / TCP/IP Layer 2: Internet Protocol: 0x0000: c4b3 01db afe2 8c85 9013 73c1 0800 4510 ..........s...E. 0x0010: 0040 0000 4000 4006 b988 ac10 011e 9bf6 .@..@.@......... 0x0020: 380b c945 0050 3c95 5fe5 0000 0000 b002 8..E.P<._....... 0x0030: ffff 6109 0000 0204 05b4 0103 0306 0101 ..a............. 0x0040: 080a 0524 e98e 0000 0000 0402 0000 ...$.......... Protocol: TCP (6) 06 Header Checksum: 0xb988 Source Address: 172.16.1.30 (ac10 011e) Destination Address: 155.246.56.11 (9bf6 380b) TCP Stuff: c945 ... 0000 $ ifconfig en0 | grep "inet " inet 172.16.1.30 netmask 0xffffff00 broadcast 172.16.1.255 $

Networking I February 24, 2020

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IPv4 Basics

10011011111101100011100000001011 IPv4 addresses are 32-bit numbers.

Networking I February 24, 2020

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IPv4 Basics

10011011 11110110 00111000 00001011 Each IPv4 address consists of four octets.

Networking I February 24, 2020

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IPv4 Basics

10011011 11110110 00111000 00001011 155 . 246 . 56 . 11 9B F6 38 0B Each IPv4 address consists of four octets.

Networking I February 24, 2020

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IPv4 Basics

10011011 11110110 00111000 00001011 IPv4 addresses are divided into a network part and a host part. Hosts on the same network (broadcast domain) can talk to each other without the help of a router.

Networking I February 24, 2020

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IPv4 Basics

10011011 11110110 00111000 00001011 There are three different classes of IPv4 networks.

Networking I February 24, 2020

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IPv4 Basics

10011011 11110110 00111000 00001011 There are three different classes of IPv4 networks. Well, five, really.

Networking I February 24, 2020

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IPv4 Basics

Networking I February 24, 2020

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Subnets

10011011 11110110 00111000 00001011 11111111 11111111 00000000 00000000 A netmask splits the IPv4 address into network and host parts.

Networking I February 24, 2020

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Subnets

10011011 11110110 00111000 00001011 11111111 11111111 11111111 00000000 A netmask splits the IPv4 address into network and host parts.

Networking I February 24, 2020

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Subnets

$ ipcalc -n 155.246.56.11/16 Address: 155.246.56.11 10011011.11110110. 00111000.00001011 Netmask: 255.255.0.0 = 16 11111111.11111111. 00000000.00000000 Wildcard: 0.0.255.255 00000000.00000000. 11111111.11111111 => Network: 155.246.0.0/16 10011011.11110110. 00000000.00000000 HostMin: 155.246.0.1 10011011.11110110. 00000000.00000001 HostMax: 155.246.255.254 10011011.11110110. 11111111.11111110 Broadcast: 155.246.255.255 10011011.11110110. 11111111.11111111 Hosts/Net: 65534 Class B Try also: sipcalc -a 155.246.56.11/16

Networking I February 24, 2020

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Subnets

$ ipcalc -n 155.246.56.11/24 Address: 155.246.56.11 10011011.11110110.00111000. 00001011 Netmask: 255.255.255.0 = 24 11111111.11111111.11111111. 00000000 Wildcard: 0.0.0.255 00000000.00000000.00000000. 11111111 => Network: 155.246.56.0/24 10011011.11110110.00111000. 00000000 HostMin: 155.246.56.1 10011011.11110110.00111000. 00000001 HostMax: 155.246.56.254 10011011.11110110.00111000. 11111110 Broadcast: 155.246.56.255 10011011.11110110.00111000. 11111111 Hosts/Net: 254 Class B Try also: sipcalc -a 155.246.56.11/24

Networking I February 24, 2020

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CIDR cheat sheet

A.B.C.D/N N = bits describing network portion of address M = 32 − N = bits in host portion of address 2M = number of addresses on this subnet 2M − 2 = number of possible hosts first address on subnet = network address last address on subnet = broadcast address subnet division need not occur on dotted boundary only for example, you can divide 155.246.89.0/24 into four /26 networks networks starting at .0, .64, .128, .192 Which of the following is not a valid netmask? 255.255.253.0, 255.255.250.0, 255.255.240.0

Networking I February 24, 2020

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Mommy, where do IP addresses come from?

The Internet Assigned Numbers Authority (IANA)

  • versees global IP address/AS number allocation,

root zone management etc. https://www.iana.org/

Networking I February 24, 2020

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Mommy, where do IP addresses come from?

Regional Internet Registries (RIR) manage the allocation and registration

  • f Internet number resources within a region of the world.

See also: https://www.xkcd.com/195/

Networking I February 24, 2020

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Mommy, where do IP addresses come from?

RIRs assign blocks of IP addresses to the Local Internet Registries (LIR). LIRs are either ISPs, enterprises using a lot of addresses, or academic institutions.

Networking I February 24, 2020

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IPv4 Subnets: Common CIDRs

10011011 11110110 00111000 00001011 | | |||| | |||||||| /32 Host route | | |||| | |||||| /30 "Glue network" (Point-to-point) | | |||| | ||||| /29 Smallest multi-host network | | |||| | |||| /28 Small LAN | | |||| | ||| /27 Small LAN | | |||| | || /26 Small LAN | | |||| | | /25 Large LAN | | |||| | /24 Large LAN | | |||| /20 Small ISP / Large business | | ||| /19 LIR / ISP / Large business | | || /18 LIR / ISP / Large business | | | /17 LIR / ISP / Large business | | /16 LIR / ISP / Large business | /8 RIR

Networking I February 24, 2020

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IPv4 Exhaustion

Networking I February 24, 2020

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IPv4 Exhaustion

IPv4 address space depletion: private IP space (RFC1918): 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 class D (224.0.0.0/4) and E (240.0.0.0/4) class As (16M addresses each!) initially handed out liberally (ATT, Apple, MIT, Stanford, Xerox, ...) subnetting often inefficient more and more devices added

Networking I February 24, 2020

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IPv4 Exhaustion

IPv4 address space depletion: Total theoretically available IP addresses: 232 RFC1918: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 RFC5735 etc.: 0.0.0.0/8, 100.64.0.0/10, 127.0.0.0/8, 169.254.0.0/16, 192.0.0.0/24, 192.0.2.0/24, 192.88.99.0/24, 198.18.0.0/15, 198.51.100.0/24, 203.0.113.0/24 Class D/E: 224.0.0.0/4, 240.0.0.0/4 ”Limited broadcast”: 255.255.255.255/32 What is the percent/number of actually available IP addresses?

Networking I February 24, 2020

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IPv4 Exhaustion

Past and predicted: IANA Address Pool Exhaustion: 2011-02-03 APNIC reached final /8: 2011-04-19 RIPENCC reached final /8: 2012-09-14 LACNIC reached final /8: 2014-06-10 ARIN reached final /8: 2015-09-24 AFRINIC (predicted): 2020-05-17 https://www.potaroo.net/tools/ipv4/ https://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml

Networking I February 24, 2020

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IPv6 Basics

10011011111101100011100000001011 IPv4 addresses are 32-bit numbers.

Networking I February 24, 2020

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IPv6 Basics

$ sudo tcpdump -w /tmp/out port 80 & $ curl -s -I http://www.yahoo.com/ >/dev/null $ fg ^C $ sudo tcpdump -t -r /tmp/out -n -XX -c 1 reading from PCAP-NG file /tmp/out.pcap IP6 2001:470:1f07:1d1:a8af:a9d:98ff:e30f.52369 > 2001:4998:58:1836::11.80: Flags [S], win 65535, options [mss 1440,nop,wscale 6,nop,nop,TS val 90153796 ecr 0,sackOK,eo 0x0000: c4b3 01db afe2 8c85 9047 b4f6 86dd 6000 .........G....‘. 0x0010: 6c64 002c 0640 2001 0470 1f07 01d1 a8af ld.,.@...p...... 0x0020: 0a9d 98ff e30f 2001 4998 0058 1836 0000 ........I..X.6.. 0x0030: 0000 0000 0011 cc91 0050 51af cc5c 0000 .........PQ..\.. 0x0040: 0000 b002 ffff aca1 0000 0204 05a0 0103 ................ 0x0050: 0306 0101 080a 055f a344 0000 0000 0402 ......._.D...... 0x0060: 0000 ..

Networking I February 24, 2020

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IPv6 Basics

OSI Layer 3 / TCP/IP Layer 2: Internet Protocol v6: 0x0000: c4b3 01db afe2 8c85 9047 b4f6 86dd 6000 .........G....‘. 0x0010: 6c64 002c 0640 2001 0470 1f07 01d1 a8af ld.,.@...p...... 0x0020: 0a9d 98ff e30f 2001 4998 0058 1836 0000 ........I..X.6.. 0x0030: 0000 0000 0011 cc91 0050 51af cc5c 0000 .........PQ.._ . 0x0040: 0000 b002 ffff aca1 0000 0204 05a0 0103 ................ 0x0050: 0306 0101 080a 055f a344 0000 0000 0402 ......._.D...... 0x0060: 0000 .. Destination address: c4:b3:01:db:af:e2 Source address: 8c:85:90:47:b4:f6 Type: IPv6 (86dd) IPv6 stuff TCP stuff $ ifconfig en0 | grep ether ether 8c:85:90:47:b4:f6

Networking I February 24, 2020

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IPv6 Basics

OSI Layer 3 / TCP/IP Layer 2: Internet Protocol v6: 0x0000: c4b3 01db afe2 8c85 9047 b4f6 86dd 6000 .........G....‘. 0x0010: 6c64 002c 0640 2001 0470 1f07 01d1 a8af ld.,.@...p...... 0x0020: 0a9d 98ff e30f 2001 4998 0058 1836 0000 ........I..X.6.. 0x0030: 0000 0000 0011 cc91 0050 51af cc5c 0000 .........PQ.._ . 0x0040: 0000 b002 ffff 751a 0000 0204 05a0 0103 ......u......... 0x0050: 0306 0101 080a 37c1 3edf 0000 0000 0402 ......7.>....... 0x0060: 0000 .. Version, Traffic Class, Flow Label, Length, Next Header; TTL: 64 (40) Source address: 2001:470:1f07:1d1:18af:0a9d:98ff:e30f Destination address: 2001:4998:58:1836::11 $ ifconfig en0 | grep inet6 inet6 fe80::1461:d52b:78a7:334a%en0 prefixlen 64 secured scopeid 0x5 inet6 2001:470:1f07:1d1:cd9:97f3:f16:eb48 prefixlen 64 autoconf secured inet6 2001:470:1f07:1d1:a8af:a9d:98ff:e30f prefixlen 64 autoconf temporary

Networking I February 24, 2020

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IPv6 Basics

0000000000100000 0000000101001001 1001100001011000 0001100000110110 0000000000000000 0000000000000000 0000000000000000 0000000000010001 IPv6 addresses are 128 bits.

Networking I February 24, 2020

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IPv6 Basics

IPv4: 32 bits => 232 addresses IPv6: 128 bits => 2128 addresses

Networking I February 24, 2020

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IPv6 Basics

IPv4: 32 bits => 4, 294, 967, 296 addresses IPv6: 128 bits => 2128 addresses

Networking I February 24, 2020

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IPv6 Basics

IPv4: 32 bits => 4, 294, 967, 296 addresses IPv6: 128 bits => 340, 282, 366, 920, 938, 463, 463, 374, 607, 431, 768, 211, 456 addresses

Networking I February 24, 2020

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IPv6 Basics

https://is.gd/94ve91

Networking I February 24, 2020

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IPv6 Basics

8x16 bit fields (words) in case insensitive colon hexadecimal representation 2031:0000:0000:030F:0000:0000:0000:130B

Networking I February 24, 2020

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IPv6 Basics

8x16 bit fields (words) in case insensitive colon hexadecimal representation 2031:0000:0000:030F:0000:0000:0000:130B Leading zeros in a field are optional: 2031:0:0:30F:0:0:0:130B

Networking I February 24, 2020

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IPv6 Basics

8x16 bit fields (words) in case insensitive colon hexadecimal representation 2031:0000:0000:030F:0000:0000:0000:130B Leading zeros in a field are optional: 2031:0:0:30F:0:0:0:130B Successive fields of 0 represented as ::, but only once in an address: 2031::30F:0:0:0:130B

  • k

2031:0:0:30F::130B

  • k

2031::30F::130B not ok

Networking I February 24, 2020

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IPv6 Basics

8x16 bit fields (words) in case insensitive colon hexadecimal representation 2031:0000:0000:030F:0000:0000:0000:130B Leading zeros in a field are optional: 2031:0:0:30F:0:0:0:130B Successive fields of 0 represented as ::, but only once in an address: 2031::30F:0:0:0:130B

  • k

2031:0:0:30F::130B

  • k

2031::30F::130B not ok 0000:0000:0000:0000:0000:0000:0000:00001 => 0:0:0:0:0:0:0:1 => ::1

Networking I February 24, 2020

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IPv6 Basics - Address Oddities

Address may include a link name: 2001:470:1f07:3d1::1%eth0

Networking I February 24, 2020

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IPv6 Basics - Address Oddities

Address may include a link name: 2001:470:1f07:3d1::1%eth0 IPv4-mapped addresses 0:0:0:0:0:ffff:66.163.162.9 ::ffff:66.163.162.9

Networking I February 24, 2020

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IPv6 Basics - Address Oddities

Address may include a link name: 2001:470:1f07:3d1::1%eth0 IPv4-mapped addresses 0:0:0:0:0:ffff:66.163.162.9 ::ffff:66.163.162.9 You need brackets to distinguish a port from an address: IPv4: 66.163.162.9:22 IPv6: [2001:470:1f07:3d1::1]:22

Networking I February 24, 2020

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IPv6 Basics – Address Scope

Link-Local (example: fe80::e276:63ff:fe72:3900%xennet0) Used on a single link Packets with link-local source or destination addresses are not forwarded to other links

Networking I February 24, 2020

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IPv6 Basics – Address Scope

Link-Local (example: fe80::e276:63ff:fe72:3900%xennet0) Used on a single link Packets with link-local source or destination addresses are not forwarded to other links Unique-Local (fc00::/7) Used for private IPv6 networks not globally routable Applications similar to RFC 1918

Networking I February 24, 2020

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IPv6 Basics – Address Scope

Link-Local (example: fe80::e276:63ff:fe72:3900%xennet0) Used on a single link Packets with link-local source or destination addresses are not forwarded to other links Unique-Local (fc00::/7) Used for private IPv6 networks not globally routable Applications similar to RFC 1918 Global (example: 2001:470:1f07:3d1::1) A globally unique address Packets with global addresses can be forwarded to any part of the global network

Networking I February 24, 2020

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IPv6 Subnets

$ sipcalc 2001:470:30:84:e276:63ff:fe72:3900/64

  • [ipv6 : 2001:470:30:84:e276:63ff:fe72:3900/64] - 0

[IPV6 INFO] Expanded Address

  • 2001:0470:0030:0084:e276:63ff:fe72:3900

Compressed address

  • 2001:470:30:84:e276:63ff:fe72:3900

Subnet prefix (masked)

  • 2001:470:30:84:0:0:0:0/64

Address ID (masked)

  • 0:0:0:0:e276:63ff:fe72:3900/64

Prefix address

  • ffff:ffff:ffff:ffff:0:0:0:0

Prefix length

  • 64

Address type

  • Aggregatable Global Unicast Addresses

Network range

  • 2001:0470:0030:0084:0000:0000:0000:0000 -

2001:0470:0030:0084:ffff:ffff:ffff:ffff

Networking I February 24, 2020

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IPv6 Subnets: Common CIDRs

2001:0db8:0123:4567:89ab:cdef:1234:5678 |||| |||| |||| |||| |||| |||| |||| |||128 Single end-points and loopback |||| |||| |||| |||| |||| |||| |||| ||124 |||| |||| |||| |||| |||| |||| |||| |120 |||| |||| |||| |||| |||| |||| |||| 116 |||| |||| |||| |||| |||| |||| |||112 |||| |||| |||| |||| |||| |||| ||108 |||| |||| |||| |||| |||| |||| |104 |||| |||| |||| |||| |||| |||| 100 |||| |||| |||| |||| |||| |||96 |||| |||| |||| |||| |||| ||92 |||| |||| |||| |||| |||| |88 |||| |||| |||| |||| |||| 84 |||| |||| |||| |||| |||80 |||| |||| |||| |||| ||76 |||| |||| |||| |||| |72 |||| |||| |||| |||| 68 |||| |||| |||| |||64 Single End-user LAN (default prefix size for SLAAC) |||| |||| |||| ||60 |||| |||| |||| |56 Proposed minimal end sites assignment |||| |||| |||| 52 |||| |||| |||48 Default end sites assignment |||| |||| ||44 |||| |||| |40 |||| |||| 36 |||| |||32 Local Internet registry minimum allocations |||| ||28 Local Internet registry medium allocations |||| |24 Local Internet registry large allocations |||| 20 Local Internet registry extra large allocations |||16 ||12 Regional Internet Registry allocations from IANA |8

Networking I February 24, 2020

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Hooray! 5 Minute Break

Networking I February 24, 2020

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Networking Buzzwords

“The network is the computer.”

John Gage, Sun Microsystems

Networking I February 24, 2020

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Networking Buzzwords

“The network is the network, the computer is the computer - sorry about the confusion.”

Joe on Computing

Networking I February 24, 2020

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Networking Buzzwords

Networking I February 24, 2020

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Networking

http://www.chrisharrison.net/index.php/Visualizations/InternetMap

Networking I February 24, 2020

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Networking

/X?

Networking I February 24, 2020

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Networking

/X?

Networking I February 24, 2020

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Networking

Networking I February 24, 2020

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WHOIS ASN?

The Internet Assigned Numbers Authority (IANA)

  • versees global IP address/AS number allocation,

root zone management etc. https://www.iana.org/

Networking I February 24, 2020

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WHOIS ASN?

Autonomous System Numbers (ASNs) are assigned by IANA to the RIRs, see e.g. ftp://ftp.arin.net/pub/stats/arin/ You can query databases on the internet about e.g. IP block or ASN information via the WHOIS protocol: $ whois 155.246.56.11 | more NetRange: 155.246.0.0 - 155.246.255.255 CIDR: 155.246.0.0/16 NetName: STEVENS NetHandle: NET-155-246-0-0-1 Parent: NET155 (NET-155-0-0-0-0) NetType: Direct Assignment Organization: Stevens Institute of Technology (SIT) RegDate: 1991-12-31 Updated: 2007-01-29 Ref: https://rdap.arin.net/registry/ip/155.246.0.0

Networking I February 24, 2020

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WHOIS ASN?

Carriers connect their Autonomous Systems at Internet Exchange Points (IXPs) to route traffic between the different networks. This peering happens amongst carriers on a tiered basis. Examples: https://peeringdb.com/net?asn=21976 https://peeringdb.com/net?asn=6939 https://peeringdb.com/net/27 https://peeringdb.com/net/433 https://peeringdb.com/net/457

Networking I February 24, 2020

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Networking

Networking I February 24, 2020

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WHOIS ASN?

Most of these services are available via APIs or text-based interfaces: $ host www.google.com www.google.com has address 172.217.0.36 www.google.com has IPv6 address 2607:f8b0:4006:807::2004 $ whois -h whois.cymru.com 2607:f8b0:4006:807::2004 AS | IP | AS Name 15169 | 2607:f8b0:4006:807::2004 | GOOGLE - Google Inc., US $ curl -s https://peeringdb.com/api/net?asn=15169 | python -mjson.tool | more { "data": [ { "aka": "Google, YouTube (for Google Fiber see AS16591 record)", "created": "2005-02-06T06:41:04Z", "id": 433, "info_ipv6": true, "info_prefixes4": 15000, "info_prefixes6": 750, "info_ratio": "Mostly Outbound",

Networking I February 24, 2020

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Networking

To find the path your packets might take, give traceroute(1) a go: $ traceroute search.yahoo.com traceroute to search.yahoo.com (63.250.200.63), 30 hops max, 60 byte packets 1 155.246.89.2 (155.246.89.2) 0.342 ms postal0.cs.stevens-tech.edu (155.246.89.3) 2 155.246.89.2 (155.246.89.2) 0.311 ms 0.300 ms gwa.cc.stevens.edu (155.246.151.3 3 454a0465.cst.lightpath.net (69.74.4.101) 3.984 ms 3.761 ms 3.735 ms 4 18267502.cst.lightpath.net (24.38.117.2) 32.559 ms 32.591 ms 32.577 ms 5 hunt183-154.optonline.net (167.206.183.154) 4.473 ms 4.634 ms 18267502.cst.ligh 6 451be0a9.cst.lightpath.net (65.19.113.169) 5.170 ms 5.278 ms hunt183-154.optonl 7 nyiix.bas1-m.nyc.yahoo.com (198.32.160.121) 6.928 ms 451be0a9.cst.lightpath.net 8 ae-1.pat2.bfw.yahoo.com (216.115.111.26) 26.422 ms ae-1.pat1.bfw.yahoo.com (216. 9 et-18-1-0.msr1.bf2.yahoo.com (74.6.227.37) 17.812 ms et-18-1-0.msr2.bf1.yahoo.co 10 et-0-1-1.clr1-a-gdc.bf1.yahoo.com (74.6.122.15) 18.817 ms et-0-1-1.clr2-a-gdc.bf1

Networking I February 24, 2020

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Networking

Networking I February 24, 2020

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Networking

Networking I February 24, 2020

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Networking

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Networking

Stringing cables across the oceans’ floors since 1866! https://www.submarinecablemap.com/ https://is.gd/CjanOu

Networking I February 24, 2020

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Networking

https://www.submarinecablemap.com/

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Networking

“The Net interprets censorship as damage and routes around it.” ...except when it can’t. https://blog.cloudflare.com/how-syria-turned-off-the-internet https://youtu.be/OZHKeYwnALc

Networking I February 24, 2020

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Networking

https://amzn.com/0061994952 https://cromwell-intl.com/travel/usa/new-york-internet/

Networking I February 24, 2020

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The internet is a physical place. https://en.wikipedia.org/wiki/Room 641A

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Networking

Now identify the physical and organizational aspects of your network traffic: $ traceroute search.yahoo.com traceroute to search.yahoo.com (63.250.200.63), 30 hops max, 60 byte packets 1 155.246.89.2 (155.246.89.2) 0.342 ms postal0.cs.stevens-tech.edu (155.246.89.3) 2 155.246.89.2 (155.246.89.2) 0.311 ms 0.300 ms gwa.cc.stevens.edu (155.246.151.3 3 454a0465.cst.lightpath.net (69.74.4.101) 3.984 ms 3.761 ms 3.735 ms 4 18267502.cst.lightpath.net (24.38.117.2) 32.559 ms 32.591 ms 32.577 ms 5 hunt183-154.optonline.net (167.206.183.154) 4.473 ms 4.634 ms 18267502.cst.ligh 6 451be0a9.cst.lightpath.net (65.19.113.169) 5.170 ms 5.278 ms hunt183-154.optonl 7 nyiix.bas1-m.nyc.yahoo.com (198.32.160.121) 6.928 ms 451be0a9.cst.lightpath.net 8 ae-1.pat2.bfw.yahoo.com (216.115.111.26) 26.422 ms ae-1.pat1.bfw.yahoo.com (216. 9 et-18-1-0.msr1.bf2.yahoo.com (74.6.227.37) 17.812 ms et-18-1-0.msr2.bf1.yahoo.co 10 et-0-1-1.clr1-a-gdc.bf1.yahoo.com (74.6.122.15) 18.817 ms et-0-1-1.clr2-a-gdc.bf1

Networking I February 24, 2020

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Internet Maps and Architecture

https://is.gd/C66S8a https://www.submarinecablemap.com/ https://en.wikipedia.org/wiki/Peering https://is.gd/tpPNE5 https://is.gd/B0d3kh https://amzn.com/0061994936 https://bgp.he.net/ https://www.wired.com/2014/08/shark_cable/

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IPv6

https://www.potaroo.net/papers/isoc/2005-07/ipv6size.html https://bgp.he.net/ipv6-progress-report.cgi https://ipv6.he.net/statistics/ https://tunnelbroker.net/

Networking I February 24, 2020