![Thinking CISCO - Fundament Basics of Telecommunications - Cisco Systems: PT Activity 2.1.7 - Troubleshooting a Serial Interface Thinking CISCO - Fundament Basics of Telecommunications - Cisco Systems: PT Activity 2.1.7 - Troubleshooting a Serial Interface](http://3.bp.blogspot.com/-xrgP2vKp1RY/UQGW1fmseaI/AAAAAAAAAw0/nV0uR-goCZw/s1600/2.png)
Thinking CISCO - Fundament Basics of Telecommunications - Cisco Systems: PT Activity 2.1.7 - Troubleshooting a Serial Interface
Refer to the exhibit. The command _show interface serial 1/0 is issued on the Router _R4, for some reason the physical line is up, but there is no connectivity between both routers.
![routing - What does the notation F0/0 and F0/1 mean in this diagram? - Network Engineering Stack Exchange routing - What does the notation F0/0 and F0/1 mean in this diagram? - Network Engineering Stack Exchange](https://i.stack.imgur.com/VWfe6.png)
routing - What does the notation F0/0 and F0/1 mean in this diagram? - Network Engineering Stack Exchange
![How to Configure Cisco Router Interfaces (FastEthernet and Serial Interfaces)-Cisco Certifications – UPaae How to Configure Cisco Router Interfaces (FastEthernet and Serial Interfaces)-Cisco Certifications – UPaae](https://upaae.com/wp-content/uploads/2016/08/config-interface-6.jpg)
How to Configure Cisco Router Interfaces (FastEthernet and Serial Interfaces)-Cisco Certifications – UPaae
![Skill Test in Packet tracer : Step by Step Basic Global Configuration commands for new learner (CISCO MODULE 1) | My Networking Learning "ABC" Skill Test in Packet tracer : Step by Step Basic Global Configuration commands for new learner (CISCO MODULE 1) | My Networking Learning "ABC"](https://mynetworkinglearningabc.files.wordpress.com/2014/07/cablling.jpg)
Skill Test in Packet tracer : Step by Step Basic Global Configuration commands for new learner (CISCO MODULE 1) | My Networking Learning "ABC"
![Serial Point-to-Point Overview (3.1) > Cisco Networking Academy Connecting Networks Companion Guide: Point-to-Point Connections | Cisco Press Serial Point-to-Point Overview (3.1) > Cisco Networking Academy Connecting Networks Companion Guide: Point-to-Point Connections | Cisco Press](https://www.ciscopress.com/content/images/chap3_9781587133329/elementLinks/03fig15_alt.jpg)
Serial Point-to-Point Overview (3.1) > Cisco Networking Academy Connecting Networks Companion Guide: Point-to-Point Connections | Cisco Press
![How to Configure Cisco Router Interfaces (FastEthernet and Serial Interfaces)-Cisco Certifications – UPaae How to Configure Cisco Router Interfaces (FastEthernet and Serial Interfaces)-Cisco Certifications – UPaae](https://upaae.com/wp-content/uploads/2016/08/config-interface-3.jpg)