A closer look at Internet structure mobile network Network edge: national or global ISP "hosts:clients and servers servers often in data centers local or Access networks,physical media: regionalSp wired,wireless communication links home network content provider etwork datacenter network enterprise network Introduction:1-11
A closer look at Internet structure Introduction: 1-11 mobile network home network enterprise network national or global ISP local or regional ISP datacenter network content provider network Network edge: ▪ hosts: clients and servers ▪ servers often in data centers Access networks, physical media: ▪wired, wireless communication links
A closer look at Internet structure mobile network Network edge: national or global ISP hosts:clients and servers servers often in data centers local or Access networks,physical media: -wired,wireless communication links home network provider network Network core: network interconnected routers ■network of networks enterprise network Introduction:1-12
A closer look at Internet structure Network edge: ▪ hosts: clients and servers ▪ servers often in data centers Access networks, physical media: ▪wired, wireless communication links Network core: ▪ interconnected routers ▪ network of networks Introduction: 1-12 mobile network home network enterprise network national or global ISP local or regional ISP datacenter network content provider network
Access networks and physical media Q:How to connect end systems mobile network to edge router? national or global ISP residential access nets institutional access networks(school, company) local or mobile access networks(WiFi,4G/5G) regionalSp What to look for: home network content provider transmission rate (bits per second)of access etwork datacenter network network? shared or dedicated access among users? enterprise network Introduction:1-13
Access networks and physical media Introduction: 1-13 mobile network home network enterprise network national or global ISP local or regional ISP datacenter network content provider network Q: How to connect end systems to edge router? ▪ residential access nets ▪ institutional access networks (school, company) ▪ mobile access networks (WiFi, 4G/5G) What to look for: ▪ transmission rate (bits per second) of access network? ▪ shared or dedicated access among users?
Access networks:cable-based access cable headend cable splitter modem V 0 0 0 0 R E E E 2 3 4 5 Channels frequency division multiplexing (FDM):different channels transmitted in different frequency bands Introduction:1-14
Access networks: cable-based access Introduction: 1-14 cable modem splitter … cable headend Channels V I D E O V I D E O V I D E O V I D E O V I D E O V I D E O D A T A D A T A C O N T R O L 1 2 3 4 5 6 7 8 9 frequency division multiplexing (FDM): different channels transmitted in different frequency bands
Access networks:cable-based access cable headend cable splitter cable modem modem CMTS termination system data,TV transmitted at different frequencies over shared cable ISP distribution network HFC:hybrid fiber coax asymmetric:up to 40 Mbps-1.2 Gbs downstream transmission rate,30-100 Mbps upstream transmission rate network of cable,fiber attaches homes to ISP router homes share access network to cable headend Introduction:1-15
Access networks: cable-based access Introduction: 1-15 cable modem splitter … cable headend data, TV transmitted at different frequencies over shared cable distribution network ▪ HFC: hybrid fiber coax • asymmetric: up to 40 Mbps – 1.2 Gbs downstream transmission rate, 30-100 Mbps upstream transmission rate ▪ network of cable, fiber attaches homes to ISP router • homes share access network to cable headend cable modem termination system CMTS ISP