If your problem is to distinguish between different blocks, then test for the delimiting "white line".

my $block=0;
 
while (<DATA>){
  if (!/^\s*$/) {
    print "$block: $_";
  } else {
    $block++;
  }
}
 
__DATA__
Mod Ports Card Type                              Model              Se
+rial No.
--- ----- -------------------------------------- ------------------ --
+---------
  1   24  CEF720 24 port 1000mb SFP              WS-X6724-SFP       SA
+L1434RA09
  3   20  7600 ES+T                              76-ES+T-20G        JA
+E14530455
  4   ...
  
Mod  Sub-Module                  Model              Serial       Hw   
+  Status
---- --------------------------- ------------------ ----------- ------
+- -------
  1  Distributed Forwarding Card WS-F6700-DFC3CXL   SAL1434RLPY  1.6  
+  Ok
  3  7600 ES+ DFC XL             7600-ES+3CXL       JAE14520N29  1.2  
+  Ok
  5  ...
[download]

now you can delegate the rest to specific one-block solution(s).