Networking interface for beginners

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I am currently learning network interfaces.



Below, using netstat, I listed interfaces with respective ports:



enter image description here



True or False



Please correct if wrong. If I were to translate this in my own words it would go like this:



  1. Anyone with ipv4 and ipv6 address can connect to my host via SSH

  2. Anyone with ipv6 address can connect to my host via http through port 80

  3. No one with ipv4 address can connect to my host via http

Question



Why is smtp bound to localhost? My understanding was that a mail server should be accessible to the outside world so computers can communicate.






linux networking







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    up vote
    0
    down vote

    favorite












    I am currently learning network interfaces.



    Below, using netstat, I listed interfaces with respective ports:



    enter image description here



    True or False



    Please correct if wrong. If I were to translate this in my own words it would go like this:



    1. Anyone with ipv4 and ipv6 address can connect to my host via SSH

    2. Anyone with ipv6 address can connect to my host via http through port 80

    3. No one with ipv4 address can connect to my host via http

    Question



    Why is smtp bound to localhost? My understanding was that a mail server should be accessible to the outside world so computers can communicate.






    linux networking







    share|improve this question







    New contributor




    e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.





















      up vote
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      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I am currently learning network interfaces.



      Below, using netstat, I listed interfaces with respective ports:



      enter image description here



      True or False



      Please correct if wrong. If I were to translate this in my own words it would go like this:



      1. Anyone with ipv4 and ipv6 address can connect to my host via SSH

      2. Anyone with ipv6 address can connect to my host via http through port 80

      3. No one with ipv4 address can connect to my host via http

      Question



      Why is smtp bound to localhost? My understanding was that a mail server should be accessible to the outside world so computers can communicate.






      linux networking







      share|improve this question







      New contributor




      e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      I am currently learning network interfaces.



      Below, using netstat, I listed interfaces with respective ports:



      enter image description here



      True or False



      Please correct if wrong. If I were to translate this in my own words it would go like this:



      1. Anyone with ipv4 and ipv6 address can connect to my host via SSH

      2. Anyone with ipv6 address can connect to my host via http through port 80

      3. No one with ipv4 address can connect to my host via http

      Question



      Why is smtp bound to localhost? My understanding was that a mail server should be accessible to the outside world so computers can communicate.






      linux networking




      linux networking






      share|improve this question







      New contributor




      e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question







      New contributor




      e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question






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      e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      e_mam106 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






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