The most common and most likely answer to this crossword clue is the 9 letter word TETHERING
I've seen this crossword clue in The Times
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More clues leading to the result TETHERING
Buddy explains!

The straight part
We know that "Securing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case securing = tethering.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TETHERING mean?
TETHERING verb- To restrict something with a tether.
- To connect a cellular smartphone to another personal computer in order to give it access to a hotspot.
- The act or means by which something is tethered.
- The connection of a personal computer to a mobile phone so as to obtain wireless Internet access from the computer.