関連ワード:  explain the role of data link layer in osi model    explain the function of data link layer    what is the role of data link layer    explain the function of data link layer in osi model    what are the responsibilities of data link layer    what are the responsibilities of data link layer in computer networks    what are the responsibilities of data link layer in internet model    what are the responsibilities of data link layer in osi model    what is the purpose of data link layer    what is the significance of data link layer