Fuzzy numbers constitute a helpful tool for some users who deal with imprecise data. To facilitate a procedure of performing operations on fuzzy numbers for these users who do not possess deep mathematical qualifications, we introduce a special space of fuzzy numbers verbally defined. This consists of families of fuzzy numbers in the L-R form provided that every family has a common mean value. We not only discuss some properties of the space, but also propose new conceptions of the arithmetical operations on the verbally expressed fuzzy numbers. The classification of the IP-traffic can act as a practical aspect, which clarifies the theoretical assumptions formulated in the paper.