Why there are 65535 ports












1















Wondering why they chose to have 16-bit (65535) ports. Why not just 256 or millions. I understand it's a power of 2, but not why it was this size. Wondering in what situations it would make sense to have a different amount, either smaller or significantly larger.






port







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  • Uh…Because TCP or UDP packet structure only have 16bit for port number?

    – 炸鱼薯条德里克
    4 mins ago











  • Obviously. I'm asking why they chose that.

    – Lance Pollard
    3 mins ago


















1















Wondering why they chose to have 16-bit (65535) ports. Why not just 256 or millions. I understand it's a power of 2, but not why it was this size. Wondering in what situations it would make sense to have a different amount, either smaller or significantly larger.






port







share|improve this question























  • Uh…Because TCP or UDP packet structure only have 16bit for port number?

    – 炸鱼薯条德里克
    4 mins ago











  • Obviously. I'm asking why they chose that.

    – Lance Pollard
    3 mins ago
















1












1








1








Wondering why they chose to have 16-bit (65535) ports. Why not just 256 or millions. I understand it's a power of 2, but not why it was this size. Wondering in what situations it would make sense to have a different amount, either smaller or significantly larger.






port







share|improve this question














Wondering why they chose to have 16-bit (65535) ports. Why not just 256 or millions. I understand it's a power of 2, but not why it was this size. Wondering in what situations it would make sense to have a different amount, either smaller or significantly larger.






port




port






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 11 mins ago









Lance PollardLance Pollard

1517




1517













  • Uh…Because TCP or UDP packet structure only have 16bit for port number?

    – 炸鱼薯条德里克
    4 mins ago











  • Obviously. I'm asking why they chose that.

    – Lance Pollard
    3 mins ago





















  • Uh…Because TCP or UDP packet structure only have 16bit for port number?

    – 炸鱼薯条德里克
    4 mins ago











  • Obviously. I'm asking why they chose that.

    – Lance Pollard
    3 mins ago



















Uh…Because TCP or UDP packet structure only have 16bit for port number?

– 炸鱼薯条德里克
4 mins ago





Uh…Because TCP or UDP packet structure only have 16bit for port number?

– 炸鱼薯条德里克
4 mins ago













Obviously. I'm asking why they chose that.

– Lance Pollard
3 mins ago







Obviously. I'm asking why they chose that.

– Lance Pollard
3 mins ago












0






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