sum_bytes

sum_bytes() {
    declare -A sum;
    while read data;
    do
        ip=$(echo $data | awk '{print $1}');
        bytes=$(echo $data | awk '{print $2}');
        if [[ ! ${sum["$ip"]} ]]; then sum[$ip]="0"; fi
        sum["$ip"]=$(expr "${sum["$ip"]}" + $bytes);
    done

    for i in "${!sum[@]}"
    do
        echo -e "$i\t${sum[$i]}";
    done
}